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CALIFORNIA   STATE   MINING   BUREAU 

FERRY  BUILDING,  SAN  FRANCISCO 
FLETCHER  HAMILTON  State  Mineralogist 

San  Francisco  BULLETIN  No.  87  January,  1920 


The  Commercial  Minerals 
of  California 


WITH  NOTES  ON  THEIR  USES,  DISTRIBUTION, 

PROPERTIES,  ORES,  FIELD  TESTS,  AND 

PREPARATION  FOR  MARKET 


BY 

W.  O.  CASTELLO 


2484 


CALIFORNIA  STATE  PRINTING  OFFICE 

SACRAMENTO 

1920 

LIBRARY 

UNIVERSITY  OF  CALIFORNIA 
DAVIS 


r'i*^^?"/f' 


IT 


CONTENTS. 

Page 

LETTER     OF     TRANSMITTAL — 8 

PREFACE    ^ 9 

ALUMINUM    — . 12 

ANTIMONY 14 

ARSENIC     — 16 

ASBESTOS     17 

ASPHALT  AND   BITUMINOUS   ROCK 19 

CARIUM-BARYTES     20 

BISMUTH    22 

BORAX 24 

("ADMIUM 25 

lEMENT  AND  LIME 1 26 

CHALK     28 

CHROMIUM     — — 28 

CLAY,   POTTERY,  BRICK,  AND  TILE 31 

COAL 32 

COPPER 33 

CORUNDUM  AND  EMERY 36 

DOLOMITE 37 

FELDSPAR     -_ 38 

FLUORSPAR  AND   CRYOLITE -- 40 

lULLER'S    EARTH    -- --_  41 

GEMS     ---  42 

GOLD     — .- 44 

GRANITE     45 

GRAPHITE 46 

GYPSUM     — 48 

INFUSORIAL  AND  DIATOMACEOUS  EARTH 49 

IRON     50 

LEAD    - ; 53 

MAGNESITE    — 55 

MANGANESE     57 

AfARBLE   — 59 

MICA   AND   LITHIA    60 

MINERAL    PAINT    62 

MINERAL    WATER    62 

MOLYBDENUM — ^ 63 

MONAZITE     _— _- 66 

NATURAL  GAS -- 67 

NICKEL 68 

NITRATES    -- 70 

PETROLEUM     72 

PHOSPHATE     ROCK     —  _ 72 

PLATINUM —  74 

POTASH     — 7G 


6  TABLE  OF   CONTENTS. 

Page 

PUMICE  AND  VOLCANIC  ASH 78 

PYRITES     — 79 

SULPHURIC   ACID    — — 81 

QUICKSILVER 81 

SALT     82 

SANDSTONE — 84 

SILICA    (SAND  AND   QUARTZ) 84 

SILVER     - 86 

SLATE     — 86 

SODA 87 

STONE,    MISCELLANEOUS 89 

STRONTIUM 90 

SULPHUR     92 

TALC-SOAPSTONE     —. 94 

TIN     95 

TUNGSTEN — --_  — 97 

VANADIUM     99 

ZINC     — _-__    101 

PHYSICAL  PROPERTIES  OF  MINERALS 105 

APPARATUS   FOR   TESTS    108 

BIBLIOGRAPHY — 110 

PUBLICATIONS  OF  THE  STATE  MINING  BUREAU 117 

INDEX     -- — 121 


LETTER  OF  TRANSMITTAL. 

January  15,  1920. 
H0NOR.VBLE  William  D.  Stephens, 

Governor  of  the  State  of  Calif arnia, 
Sacramento,  California. 

Sir:  I  have  the  honor  to  transmit  herewith  Bulletin  No.  87  of 
the  State  Mining  Bureau,  entitled  ''The  Commercial  Minerals  of 
California." 

This  bulletin  is  the  compilation  of  a  series  of  articles  which  were 
prepared  in  the  form  of  w-eekly  press  bulletins  sent  to  representative 
newspapers  throughout  the  state  beginning  June,  1918,  for  the  purpose 
of  giving  practical  information  on  California's  great  variety  of  mineral 
products  and  to  stimulate  production  during  a  time  of  need. 

It  is  believed  the  data  is  of  sufficient  value  to  warrant  its  publica- 
tion in  this  form,  for  general  distribution  to  the  public,  w^ho  may  be 
interested  in  the  development  of  our  raw^  materials. 

IS  Respectfully  submitted. 

P  Fletcher  Hamilton, 

State  Mineralogist. 


PREFACE. 

The  headquarters  of  the  California  State  Mining  Bureau  are  located 
on  the  third  floor  of  the  Ferry  Building,  San  Francisco,  and  consist 
of  the  administrative  offices  of  the  State  Mineralogist,  State  Supervisor 
of  Petroleum  and  Gas,  Library,  Mineral  Museum,  and  other  offices 
necessary  for  carrying  on  the  work  of  the  bureau.  Field  branches 
have  been  established  at  the  following  points:  Los  Angeles  (512  Union 
League  Building),  Santa  Paula,  Santa  Maria,  Bakersfield,  Taft,  Coal- 
inga.  East  Auburn,  and  Redding.  The  institution  is  supported  by 
legislative  appropriation,  and  is  under  the  direction  of  Fletcher  Hamil- 
ton, State  Mineralogist.  Its  purpose  is  to  promote  the  interests  of 
the  mineral  industry  in  California  in  every  possible  way.  This  object 
is  accomplished  by  various  means,  briefly  outlined  as  follows: 

PUBLICATIONS. 

Bulletins,  reports,  and  maps,  covering  all  phases  of  the  mining  indus- 
try of  the  state,  compiled  as  a  result  of  the  work  of  mining  engineers 
and  geologists  in  the  field,  are  available  for  reference  and  distribution 
upon  application  at  this  office.  It  is  possible  to  distribute  some  of 
these  publications  free  of  charge,  but  for  those  more  elaborate  and 
detailed  a  nominal  price  is  asked.     (See  list  of  publications,  page  117.) 

GENERAL  INFORMATION  BUREAU. 

An  information  desk  is  manitained  at  the  main  office  of  the  Bureau  in 
the  Ferry  Building,  and  the  entire  staff  of  assistants  is  at  the  service 
of  the  public  at  all  times  in  this  regard.  All  personal  and  written 
inquiries  relative  to  any  phase  of  mining  or  the  occurrence  of  mineral 
substances  in  California,  are  given  careful  and  immediate  attention. 

LIBRARY. 

The  Bureau  Library  contains  over  5000  volumes  of  selected  works 
including  government,  state  and  individual  reports  on  mines  and  mining 
and  allied  technical  subjects,  as  well  as  files  of  the  leading  technical 
magazines  of  the  world,  together  with  the  current  copies  of  the  local 
papers  from  the  majority  of  the  mining  camps  of  California.  Here  may 
also  be  found  for  reference  count}'  maps,  topographical  sheets,  geo- 
logical folios,  etc.  A  reading  room  is  maintained  in  conjunction  with 
the  Library,  and  both  are  open  to  the  public  daily  from  9  a.m.  until 
5  p.m.,  except  Sundays  and  holidays;  and  from  9  a.m.  to  12  m.  Satur- 
days. 

LABORATORY. 

Samples  limited  to  three  at  one  time,  of  any  mineral  found  in  the 
state,  may  be  sent  to  the  Bureau  for  identification,  and  the  same  will  be 
classified  free  of  charge.     The  Bureau  is  not  authorized  to  make  deter- 


10  CALIFORNIA    STATE    MINING   BUREAU. 

minations  on  samples  received  from  points  outside  the  state.  It  must 
also  he  understood  that  no  assays  or  quantitative  analysis  can  be  made. 
Samples  should  be  in  lump  form  if  possible,  and  marked  plainly  with 
name  of  sender  on  outside  of  package.  No  samples  will  be  received 
unless  delivery  charges  are  prepaid,  and  a  letter  should  be  forwarded  at 
the  same  time,  stating  the  general  locality  where  the  mineral  was  found. 
and  the  exact  nature  of  the  information  desired.  The  work  of  this 
department  is  especially  reliable,  and  many  thousand  prospectors  and 
others  have  taken  advantage  of  the  assistance  which  is  offered  in  this 
manner. 

MUSEUM. 

The  Museum,  which  occupies  the  entire  north  wing  of  the  third 
floor  of  the  Ferry  Building,  with  a  floor  space  of  7500  scjuare  feet,  is 
one  of  the  finest  in  the  country.  A  complete  mineralogical  study  of 
California  may  be  carried  on  from  the  20,000  mineral  specimens  to  be 
seen,  attractively  arranged  in  this  immense  exhibit.  Aside  from  its 
purely  scientific  interest  the  Museum  daily  attracts  throngs  of  tourists 
and  sightseers,  and  has  accomplished  a  great  deal  in  the  w^ay  of  giving 
visual  evidence  of  California's  A^ast  mineral  resources. 

STATISTICAL    DEPARTMENT. 

Since  1894  the  Bureau  has  annually  issued  a  special  bulletin  covering 
in  detail  the  actual  mineral  production  of  the  state  for  the  preceding 
year.  Data  covering  the  amount  and  value  of  the  yearly  output  is 
received  by  the  statistical  department  from  every  individual  mineral 
operator  in  California,  and  these  returns,  when  classified  and  published 
in  county  totals,  give  the  clearest  possible  conception  of  the  various 
sections  of  the  state,  and  have  proven  in  the  past  to  be  of  great  aid  to 
prospective  investors  and  others  interested.  It  is  to  the  undoubted 
interest  of  every  owner  and  operator  of  a  mineral  property  in  Cali- 
fornia to  cooperate  with  the  Bureau  in  its  efforts  to  collect  reliable  and 
authoritative  statistical  data. 

DEPARTMENT  OF  PETROLEUM  AND  GAS. 

This  department  was  established  by  law  August  9,  1915.  It  is  under 
the  general  jurisdiction  of  the  State  Mineralogist,  who  is  authorized 
to  appoint  a  supervisor  and  engineer  or  geologist  experienced  in  the 
development  and  production  of  petroleum.  It  is  the  duty  of  the  super- 
visor to  supervise  the  drilling,  operation,  maintenance  and  abandonment 
of  petroleum  or  gas  wells,  so  as  to  prevent  damage  to  these  deposits 
from  infiltrating  water  and  other  causes.  It  is  of  vital  interest  to  the 
general  public  that  waste  of  the  natural  supply  of  petroleum  and  gas 
in  California  be  prevented,  and  it  is  believed  that  the  farsightedness  of 
the  framers  of  this  law  has  been  inlly  exemplified  in  the  short  time 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  11 

which  has  elapsed  since  the  work  in  this  department  was  first  inaugu- 
rated, on  account  of  the  practical  results  which  have  followed  it.  Much 
of  the  damage  caused  in  the  past  has  been  due  to  lack  of  knowledge  of 
imderground  conditions.  Information  in  this  regard  is  being  constantly 
Lrathered  and  systematized  by  the  Bureau,  and  the  result  placed  at  the 
disposal  of  the  oil  operators. 

WAR    ACTIVITIES. 

Soon  after  our  declaration  of  war  with  Germany  it  became  apparent 
that  this  country  would  be  thrown  upon  its  own  resources  for  many 
mineral  substances  which,  in  the  past,  had  been  largely  imported. 
The  war  program  for  increased  construction  and  manufacture  also  made 
necessary  a  great  increase  in  the  production  of  many  minerals,  ores 
and  structural  materials  which  had  for  some  time  been  produced  in 
quantities  only  approximately  equal  to  pre-war  consumption. 

Since  California  produces  a  greater  number  of  commercial  mineral 
substances  than  any  other  state  in  the  Union,  and  was  one  of  the  fore- 
most producers  of  several  of  the  war  minerals,  a  large  responsibility 
was  thrown  upon  the  miners  and  producers  of  this  state. 

Among  other  things  which  the  State  Mining  Bureau  undertook  in 
order  to  bring  the  situation  more  forcibly  to  the  attention  of  those 
directly  concerned,  and  to  stimulate  production,  was  the  preparation 
of  weekly  articles,  each  dealing  with  some  mineral  substance  which 
has  been  produced  or  found  in  California.  These  articles  were  sent 
to  newspapers  in  every  section  of  the  state,  for  publication,  and  extra 
copies  were  kept  on  file  at  the  main  office  and  the  several  branch  offices 
of  the  Alining  Bureau,  for  free  distribution.  They  also  served  in 
answering  many  inquiries,  both  personal  and  written  in  regard  to 
general  information  as  to  demand,  production,  price,  etc.,  of  the  many 
minerals  dealt  with. 

The  data  given  does  not  pretend  to  be  more  than  a  compilation  of 
available  material  from  many  sources,  presented  in  a  way  intended  to 
irive  concise  and  practical  information  to  the  prospector,  miner,  pro- 
ducer, or  anyone  interested  in  the  mineral  industry. 

Publications  of  the  United  States  Geological  Survey  have  been  freely 
drawn  upon  for  figures  relative  to  total  production,  imports,  etc.,  as 
well  as  other  general  information;  also  numerous  reports  and  bulletins 
of  the  State  Mining  Bureau,  as  well  as  the  standard  text  books  on 
the  sub.iects,  all  mentioned  hereafter  in  the  bibliography. 

Note — When  the  material  was  sent  out  in  the  form  of  weekly  articles,  informa- 
tion relative  to  demand,  production  and  value  of  the  various  minerals  was  included; 
but  all  three  factors  are  constantly  changing.  Up  to  date  data  covering  these 
facts  may  always  be  obtained  from  the  Bureau's  annual  statistical  report,  wh'ch 
is  distributed  free  of  charge.  It  is  therefore  suggested  that  those  interested  in 
demand,  production,  or  value,  provide  themselves  with  the  latest  statistical  report, 
a  copy  of  which  will  gladly  be  forwarded  to  any  address  immediately  upon  request. 


12  CALIFORNIA    STATE    MINING   BUREAU. 


ALUMINUM. 

The  most  important  domestic  consumption  of  aluminum  in  the  past 
few  years  was  directly  or  indirectly  in  the  war  industries.  It  was 
used  in  a  great  variety  of  forms,  in  the  manufacture  of  war  apparatus. 

There  has  been  no  production  of  aluminum  in  California,  although 
small  deposits  of  impure  raw  material  have  been  reported.  Approxi- 
mately 70%  of  the  nation's  output  is  used  in  the  manufacture  of 
aluminum,  the  remainder  being  utilized  in  making  chemicals,  salts, 
abrasives  and  refractories.  Although  the  domestic  consumption  has 
greatly  increased,  the  home  deposits  have  apparently  been  able  to 
supply  the  demand,  leaving  some  ore  for  export. 

The  principal  markets  are  east  of  the  Mississippi. 

Industrial  application  and  uses. 

Aluminum  is  used  in  the  manufacture  of  aeroplanes,  ships,  auto- 
mobiles, and  a  great  many  other  appliances,  in  the  form  of  castings, 
plates,  metallic  parts  and  fittings,  drawn  and  pressed  wire  and  pro- 
tective coatings.  In  many  small  ways  it  goes  into  the  makeup  of  the 
soldier's  equipment.  Aluminum  powder  is  used  to  some  extent  in 
high  explosives.  A  great  amount  is  consumed  in  the  manufacture  of 
cooking,  household  and  industrial  utensils,  scientific  apparatus,  surgical 
instruments  and  various  alloys.  Most  of  these  uses  are  due  to  the 
properties  of  lightness  and  resistance  to  the  action  of  the  atmosphere. 

Aluminum  salts,  such  as  aluminum  and  sodium  alums,  aluminum 
sulphate  and  aluminum  chloride  are  also  made  in  the  United  States. 
Some  of  these  are  used  in  making  baking  powder  and  dyes. 

Properties  and  ores. 

The  pure  metal  aluminum  is  bluish  white  in  color,  has  a  metallic  lus- 
ter and  is  very  light,  its  specific  gravity  being  2.6.  It  is  very  ductile 
and  malleable,  may  be  cast  and  welded,  is  a  good  conductor  of  heat 
and  electricity  and  is  not  readily  oxidized  in  the  air. 

The  principal  commercial  ore  is  bauxite,  a  hydrous  oxide  of  alum- 
inum (AUO3.  2II2O).  Contains  73.9%  AUG, +  26.1%  H.O.  It  resem- 
bles ordinary  clay,  being  white,  yellow,  brown  or  red  in  color,  very 
soft  (hardness  1.5)  and  quite  light  (gravity  2.5).  Massive  and  earthy 
in  structure  and  commonly  impure  through  the  presence  of  iron  oxides, 
silica,  lime  and  magnesia.  It  received  its  name  from  the  village  of 
Px'aux  in  France,  where  it  was  found  in  1821. 


I 


COMMERCIAL    MINERALS   OF   CALIFORNIA.  13 

Distribution. 

Although  aluminum  does  not  occur  free  in  nature,  its  compounds 
are  numerous  and  widely  distributed.  It  is  the  most  common  of  the 
metals,  making  up  about  S%  of  the  earth's  crust.  Many  common 
rocks  and  minerals  are  silicates  and  oxides  of  aluminum,  with  other 
metals.  Clays  and  slates  are  mainly  silicates  of  aluminum  formed 
by  the  decomposition  of  other  minerals.  The  common  feldspars  con- 
tain from  20%  to  35%  aluminum.  Corundum  is  aluminum  oxide 
(AloOg)  and  the  precious  stones,  ruby  and  sapphire,  are  varieties  of 
this  mineral,  the  color  being  given  by  oxides  of  the  other  metals. 
The  precious  stones,  topaz,  amethyst,  and  Oriental  emerald  are  silicates 
of  aluminum.  Although  the  metal  is  so  widely  distributed  in  these 
various  minerals  mentioned,  it  is  not  produced  commercially  from  them. 

As  previously  mentioned,  pure  deposits  of  the  commercial  ore  bauxite 
have  not  been  found  in  California.  Impure  varieties  have  been  found 
in  Yuba  and  Riverside  counties.  The  known  commercial  deposits  in 
the  United  States  are  in  Arkansas,  Alabama,  Georgia  and  Tennessee. 

In  general  occurrence  it  is  closely  associated  with  kaolin  or  claj', 
and  is  derived  from  the  alteration  of  syenite  or  the  action  of  circulating 
waters  on  shales,  limestones,  and  quartzitic  rocks. 

Tests. 

Infusible  aluminum  compounds,  or  minerals,  when  moistened  with 
cobalt  nitrate  and  intensely  heated  before  the  blow  pipe,  assume  a 
line  blue  color.  The  mineral  should  be  powdered  and  heated  either 
on  charcoal  or  on  the  loop  of  a  platinum  wire.  Ammonia,  when 
added  in  excess  to  an  acid  solution  containing  aluminum,  precipitates 
gelatinous  aluminum  hydroxide.  Bauxite  may  be  tested  by  the  first 
method  given.  It  is  insoluble  or  only  slightly  soluble  in  hydrochloric 
acid. 

Preparation. 

Aluminum  is  produced  by  treating  AL.Og  (purified  bauxite)  with  an 
electric  current,  in  a  fused  bath  of  cryolite  (AlgNgGFjo).  The  process 
is  carried  on  in  large  iron  pots  with  thick  carbon  lining. 

Bauxite  is  purified  by  heating  with  soda,  forming  a  soluble  alum- 
inate.     The  ferric-oxide  contained  in  the  ore  is  unaltered. 

3Na,C03+AUO,=2Na3A10,+3CO,. 

The  mass  is  washed  on  a  large  filter,  and  the  pure  Al(OH);j  pre- 
cipitated from  the  solution  by  agitation  with  carbon  dioxide  (CO;,), 
obtained  from  limestone.  This  Al(HO)..,  after  settling,  is  washed 
on  a  filter  or  in  a  centrifugal  machine. 


14  CALIFORNIA    STATE    MINING   BUREAU. 

In  the  Bayer  process  a  solution  of  sodium  aluminate  is  prepared, 
and  by  stirring  powdered  aluminum  into  this  a  crystalline  precipitate 
of  aluminum  hydroxide  separates,  the  impurities  remaining  in  solu- 
tion. Under  certain  conditions,  when  powdered  bauxite  is  added  to 
this  solution  and  stirred  vigorously,  more  aluminum  is  dissolved  out 
of  the  bauxite,  and  a  cycle  of  operations  result. 

ANTIMONY. 

The  demand  for  antimony  in  the  United  States  has  in  the  past  been 
almost  entirely  supplied  by  imports,  mostly  from  China,  Japan.  ^Mexico 
and  Europe. 

Deposits  of  this  metal  in  California  have  been  one  of  the  dormant 
mineral  resources  of  the  state.  Occasionally  a  small  production  has 
been  reported;  none,  however,  appeared  from  1902  to  1915.  With  the 
beginning  of  the  war  and  the  increased  demand  for  antimony  in  the 
manufacture  of  munitions,  prices  rose  from  a  normal  of  7^  or  8^  per 
pound  for  the  metal  to  40^  per  pound  at  the  end  of  1915.  This  re- 
newed interest  in  known  deposits  in  this  state  and  stimulated  the  search 
for  new  ones,  and  the  result  was  a  small  production  in  1915,  1916 
and  1917. 

Industrial  application  and  uses. 

In  the  war  industries  antimony  is  used  with  lead  in  the  manufacture 
of  bullets,  shrapnel,  etc.  Its  function  is  to  harden  the  lead.  Anti- 
mony sulpbide  is  used  in  smoke  bombs  and  primers  of  shells  and 
cartridges.  In  peace  times  its  greatest  use  is  in  the  making  of  alloys 
such  as  type  metal  and  anti-friction  metals,  because  of  its  peculiar 
property  of  expanding  when  cooling  from  a  molten  state,  thus  insuring 
sharp,  clean-cut  edges.  Some  of  its  compounds  are  used  in  the  manu- 
facture of  color  pigments  and  paints  and  in  medicine  | 

Properties  and  ores. 

Native  antimony  (Sb.)  is  a  tin-white  metal  with  a  fine  metallic 
luster,  generally  massive,  but  sometimes  granular,  has  a  distinct  lam- 
ellar structure  and  perfect  basal  cleavage.  It  is  very  brittle  and 
heavy   (specific  gravity  6.6-6.7),  but  not  hard   (hardness  3.0-3.5). 

Stibnite  (SbgSa),  antimony  sulphide,  is  the  common  ore  of  antimony. 
Contains  71.4%  antimony  and  28.6%  sulphur.  It  is  lead-gray  to 
dark-gray  in  color,  with  dark-gray  streak.  Has  a  metallic  luster,  per- 
fect cleavage  and  uneven  fracture.  Very  soft  (hardness  2.0)  ;  specific 
gravity  4.5-4.6.     Generally  occurs  in  long  prismatic  crystals  often 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  15 

bent  or  curved  with  faces  striated  or  furrowed.     Sometimes  occurs 
massive  or  granular. 

Distribution. 

Antimony  in  very  small  amounts  is  a  constituent  of  many  minerals 
and  ores.  Thus  widely  distributed  it  is  of  no  commercial  value  and  is 
often  a  detriment  to  the  treatment  of  ores  for  other  metals. 

Stibnite  occurs  in  veins  in  granite  and  metamorphic  gneisses  and 
schists,  and  is  closely  associated  with  the  common  sulphides  of  lead, 
zinc,  copper,  and  iron,  i.  e.,  galena,  sphalerite,  chalcopyrite,  pyrite  and 
tetrahedrite.  It  is  also  often  associated  with  mercury  and  arsenic. 
It  occurs  in  gold-bearing  quartz  veins  and  has  a  strong  tendency  to 
form  replacements  in  limestone  and  shale.  Its  decomposition  near 
the  surface  results  in  various  yellowish  and  white  oxides. 

The  better  known  deposits  in  California  are  in  Kern,  Inyo,  River- 
side, San  Benito,  and  Santa  Clara  counties.  It  has  been  found  in 
^Mariposa,  Merced,  Mono,  Nevada,  Sierra  and  Calaveras  counties  also. 

Tests. 

Stibnite  fuses  readily  in  the  flame  of  a  candle,  and  when  heated 
before  the  blowpipe  on  charcoal,  is  absorbed,  giving  off  white  fumes 
which  have  no  distinct  odor,  and  which  form  a  white  coating  on  the 
charcoal.  When  heated  in  the  open  tube,  oxides  of  antimony  are 
formed  and  deposited  on  the  sides  of  the  tube,  sometimes  as  a  ring 
near  the  heated  part  and  sometimes  all  along  the  under  side  of  the 
tube,  and  often  dense  white  fumes  are  given  off.  When  treated  with 
concentrated  nitric  acid  a  white  substance  is  formed  which  is  very 
insoluble  in  water. 

Metallurgy. 

Stibnite  is  either:  (1)  reduced  directly  by  metallic  iron;  or  (2) 
roasted  to  oxide,  and  then  reduced  by  charcoal.  The  ore  is  ground 
fine,  mixed  with  iron  scrap  and  turnings,  and  salt  or  salt  cake,  and 
put  into  crucibles  each  holding  about  60  pounds.  Scrap  iron  is  placed 
on  top  and  the  crucibles  are  then  placed  in  a  long,  narrow  reverberatory 
furnace.  The  salt  acts  as  a  flux.  SboSg  +  3Fe  =  2Sb  +  3FeS. 
The  product,  after  removal  from  the  furnace,  contains  several  per  cent 
of  iron,  and  this  is  removed  by  a  second  heating  with  clean  stibnite. 
The  sulphur  is  removed  by  a  third  heating  with  potash  or  soda. 

In  the  other  method  the  ore  is  simply  roasted  to  oxide: 

2Sb.S3  -f  90.  =  2Sb203  -[-  680^ 
and  this  reduced  by  heating  with  charcoal: 

2Sb,03  +  3C  =  4Sb  -f  SCO,. 


16  CALIFORNIA    STATE    MINING   BUREAU. 

ARSENIC. 

Arsenic  was  first  produced  in  the  United  States  in  1901  from  a 
plant  at  Everett,  Washington. 

Industrial  application  and  uses. 

Arsenic  is  used  in  the  form  of  arsenious  acid  (AS0O3)  in  dyeing 
and  printing  cloth,  in  the  manufacture  of  pigments,  soaps,  and  other 
salts  of  arsenic,  and  in  preserving  skins  of  animals  and  birds.  The 
metal  is  used  to  harden  lead  in  making  bullets,  shot,  etc..  and  to  some 
extent  in  other  alloys. 

Properties  and  ores. 

Arsenic  occurs  free  in  nature  as  a  brittle,  tin-white  or  steel-gray 
metal.  When  freshly  broken  it  has  a  metallic  luster,  but  tarnishes 
quickly  to  almost  black  in  moist  air.  Hardness  3.5,  specific  gravity 
5.6-5.7.  When  heated  in  the  air  it  volatilizes,  giving  off  a  garlic  odor. 
Occurs  associated  with  antimony  and  ores  of  gold  and  silver.  The 
arsenic  of  commerce  is  rarely  obtained  from  the  metal,  but  from 
arsenopyrite,  while  the  commercial  arsenious  acid  is  obtained  as  a 
by-product  in  the  extraction  of  nickel,  cobalt  and  silver  from  their 
ores. 

Arsenopyrite  (FeAs^)  Arsenical  pyrites.  Called  also  mispickel. 
Color  silver-white  or  steel-gray,  metallic  luster,  brittle,  hardness 
5.5-6.0,  specific  gravity  5.9-6.2.  Contains  46%  arsenic,  19.7%  sulphur 
and  34.3%  iron.  Occurs  generally  in  crystalline  rocks,  associated  with 
ores  of  silver,  gold,  tin  and  lead. 

Realgar  (AsS)  and  Orpiment  (AS2S3),  sulphides  of  arsenic,  although 
not  used  as  ores  of  arsenic,  have  a  certain  commercial  value.  Realgar 
is  orange  yellow  to  red  in  color,  resinous  luster,  hardness  1.5-2.0, 
specific  gravity  5.7.  Contains  70.1%  arsenic  and  29.9%  sulphur. 
Orpiment  is  lemon  yellow  in  color  with  properties  similar  to  realgar 
and  contains  61 9^  arsenic  and  39%  sulphur.  The  minerals  are  closely 
associated  and  usually  found  together.  Realgar  is  used  for  pyrotech- 
nic displays,  yielding  a  brilliant  white  light,  while  orpiment  is  used 
in  dyeing  and  in  a  preparation  to  remove  hair  from  skin. 

Distribution. 

Arsenopyrite  is  a  common  vein  mineral  in  the  state  and  is  often  gold 
bearing,  in  fact  in  some  gold  districts  it  is  the  chief  gold  ore.  It  has 
not  yet  been  used  in  California,  however,  for  the  production  of  arsenic. 

Realgar  has  occasionally  been  found  in  California  associated  with 
other  ores,  but  it  is  very  rare. 


COMMERCIAL    MINERALS   OP    CALIFORNIA.  17 

Tests. 

When  arsenic  or  its  sulphides  are  heated  on  charcoal  before  the 
blowpipe,  the  arsenic  volatilizes,  combines  with  oxygen  of  the  air 
forming  AS2O3,  which  condenses  as  a  white  coating  on  the  charcoal 
some  distance  away  from  the  assay.  When  heated  in  the  reducing 
flame,  the  fumes  given  off  have  a  disagreeable  garlic-like  odor  which 
is  very  characteristic  and  easily  recognized. 

When  heated  in  the  open  tube  the  white  sublimate  condenses  as  a 
ring  on  the  sides  of  the  glass.  The  coating  is  volatile  and  disappears 
when  heated. 

Arsenopyrite  fuses  before  the  blowpipe  to  a  strongly  magnetic 
globule. 

Realgar  and  orpiment  when  heated  in  the  closed  tube  give  a  deep 
red  almost  black  liquid  sublimate  when  hot  which  becomes  a  reddish 
yellow  transparent  solid  when  cold. 

Metallurgy. 

Metallic  arsenic  is  obtained  from  arseno-pyrite  by  a  combined  system 
of  retorts  and  condensers.     A  simple  decomposition  takes  place. 

FeAsS  =  FeS  +  As 

White  arsenic  (AsoOg)  is  obtained  by  roasting  either  arseno-pyrite 
or  the  flue  dust,  resulting  from  the  smelting  of  certain  lead,  copper 
or  tin  ores. 

ASBESTOS. 

The  production  of  asbestos  in  the  United  States  is  far  less  than  the 
demand.  The  output  in  California  has  been  very  small  and  intermit- 
tent.    A  great  portion  of  the  world  supply  comes  from  Canada. 

Industrial  application  and  uses. 

The  greatest  and  most  common  use  for  asbestos  is  in  making  fire- 
proof material,  such  as  theater  curtains,  firemen's  clothing,  wrappings 
for  steam  and  hot  water  pipes,  furnace  linings,  packings  for  pistons 
and  cylinder  heads,  and  small  household  articles.  It  is  also  ground 
and  made  into  cements,  paints,  brick,  tiling,  plaster,  flooring,  roofing 
and  insulating  material. 

Properties  and  ores. 

In  its  original  sense  asbestos  was  a  fibrous  variety  of  the  mineral 
amphibole.  a  metasilicate  of  calcium,  magnesium  and  iron.  As  now 
used  the  term  includes  tremolite,  and  actinolite  (amphiboles),  and 
chrysotile,  a  hydrous  silicate  of  magnesia,  being  a  fibrous  form  of 
serpentine. 

2-24S4 


18  CALIFORNIA   STATE    MINING  BUREAU. 

Amphibole  asbestos  possesses  high  refractory  properties,  but  lacks 
strength  of  fibre  and  is  used  mainly  for  covering  steam  pipes  and 
boilers,  while  chrysotile  fibres  are  often  of  silky  fineness,  and  have 
greater  strength  and  elasticity  and  may  be  spun  into  threads  or  woven 
into  cloth. 

To  bring  the  highest  market  price,  asbestos  must  possess  the  following 
properties :  toughness  or  tensile  strength,  inf usibility,  flexibility,  length 
and  fineness  of  fibre.  The  most  important  of  these  are  toughness  and 
infusibility.  It  must  be  kept  in  mind  that  the  length  of  fibre,  the 
characteristic  that  most  strongly  appeals  to  the  eye,  is  not  the  final 
test  for  the  commercial  value  of  the  ore,  but  given  samples  of  equal 
quality  otherwise,  the  ore  with  the  longest  fibre  will  of  course  be  the 
most  valuable. 

As  found  in  nature  asbestos  is  white,  gray,  green  or  yellow  in  color, 
generally  soft  (hardness  2.5-5.0)  and  light  (specific  gravity  2.5-2.6). 
It  has  a  greasy  luster  and  feels  smooth  and  greasy.  The  fibrous 
structure  is  its  most  striking  characteristic. 

Distribution. 

Asbestos  of  various  grades  is  widely  distributed  in  California,  but 
the  deposits  have  been  considered  mostly  of  such  low  quality,  that 
the  material  has  not  been  marketed.  Commercial  production  has  been 
made  in  Alameda,  Calaveras,  Inyo,  Nevada  and  Shasta  counties.  One 
firm  has  a\,  grinding  and  fibreizing  plant  in  Oakland,  and  a  new  mill 
has  recently  been  put  in  operation  at  Washington^,  in  Nevada  County. 

The  greater  part  of  the  United  States  supply  comes  from  Quebec, 
Canada,  where  there  are  large  deposits  of  excellent  quality  and  all 
grades.  This  supply  is  so  convenient  that  it  has  tended  to  delay  the 
development  of  home  deposits. 

Production  has  been  made  to  some  extent  in  Arizona,  Georgia,  Idaho 
and  Virginia. 

Tests. 

Asbestos  is  readily  distinguished  by  its  fibrous  structure,  infusibility 
and  other  physical  characteristics  described  under  Properties.  The 
hydrochloric  acid  solution,  if  dilute,  gives  an  abundant  precipitate 
with  sodium  phosphate  (test  for  magnesium). 

Preparation. 

The  longer  more  flexible  fibres  are  spun  or  woven  into  cloth,  while 
the  short  non-elastic  material  is  ground  and  pressed  into  sheets,  or 
bricks,  or  used  for  paint,  etc. 


i 


COMMERCIAL    MINERALS   OF    CALIFORNIA.  19 

ASPHALT   AND    BITUMINOUS    ROCK. 

Before  the  oil  industry  grew  to  such  proportions  in  California, 
asphalt  was  produced  from  outcroppings  of  oil  sands,  and  was  rated 
as  a  separate  industry.  In  the  last  few  years,  however,  almost  all  of 
the  asphalt  has  come  from  the  oil  refineries,  which  produce  a  more 
uniform  product  of  better  quality  than  is  found  in  natural  deposits. 

The  production  of  asphalt  from  14  refineries  in  California  in  1917 
was  approximately  220,300  tons,  valued  at  $2,100,252.  This  is  the 
largest  producing  state  in  this  regard,  as  the  crude  oils  are  almost 
entirely  of  asphalt  base.  The  refinery  of  the  Standard  Oil  Company 
at  Richmond,  Contra  Costa  County  is  the  largest  in  the  world. 

The  natural  asphalt  that  is  mined  at  present  is  in  the  form  of 
bituminous  sandstone,  used  for  road  material.  The  production  in  1918 
was  from  one  quarry  each  in  Santa  Cruz,  San  Luis  Obispo  and  Santa 
Barbara  counties,  and  amounted  to  2561  tons,  valued  at  $9,067. 
Other  important  producing  states  are  Texas,  Oklahoma,  Utah,  Ken- 
tucky and  Colorado.  Large  quantities  are  annually  imported  from 
Trinidad,  one  of  the  West  India  Islands,  and  from  Venezuela. 

The  war  stimulated  domestic  markets  for  asphalt  material  derived 
from  crude  petroleum,  and  for  imported  asphalt,  but  the  abundance 
of  these  materials  has  lessened  the  demand  for  native  bitumens  and 
for  various  types  of  bituminous  rock  produced  in  this  country. 

Industrial  application  and  uses. 

Bituminous  rock  is  used  principally  as  a  road-building  material. 
Other  varieties  of  natural  asphalt  are  used  in  the  manufacture  of 
roofing  material,  paints,  varnishes,  rubber  substitutes  and  paving 
cements.  Some  natural  asphalts  are  used  directly  as  paving  and 
road  surfacing  material. 

Properties. 

The  hydrocarbons,  as  the  name  implies,  are  composed  of  hydrogen 
and  carbon  in  widely  varying  proportions.  The  term  includes  a  large 
group  of  materials  ranging  from  the  gaseous  state,  such  as  marsh  gas, 
or  natural  gas,  through  the  liquids,  as  petroleum  and  its  products,  to 
the  solid  coals. 

Bitumen,  as  commonly  used,  is  a  somewhat  narrower  term,  which, 
while  it  may  embrace  all  the  hydrocarbons,  is  generally  applied  to  the 
semi-solid  or  viscous  materials,  as  asphalt,  tar  and  heavy  oils.  Asphalt 
is  a  dense,  black,  heavy,  semi-solid  material,  one  of  the  products  from 
the  refining  of  crude  petroleum. 

Layers  of  bitumen  and  seepages  of  viscous  tar-like  matter  are  com- 
mon in  the  Monterey  and  San  Pablo  shales  and  sandstones,  and  are 
found  in  commercial  quantities  where  these  formations  are  exposed. 


20  CALIFORNIA    STATE    MINING   BUREAU. 

Tests. 

Asplialt  and  bituminous  material  can  be  readily  distinguished  by 
the  ease  with  which  it  burns,  and  by  its  soft,  black,  oily  or  pitch-like 
appearance.  When  in  the  harder  or  more  compact  state  it  has  a 
prominent  conchoidal  fracture.  Has  a  distinguishing  bituminous  odor 
and  taste. 

BARIUM-BARYTES. 

The  barium  industry  in  the  United  States  has  shown  a  remarkable 
growth  in  the  past  few  years.  This  increase  was  due  to  the  establish- 
ment of  the  barium  chemicals  industry  in  the  United  States,  the  in- 
creased manufacture  of  lithopone,  greater  use  of  ground  barytes, 
particularly  in  the  rubber  industry,  and  the  curtailment  of  imports. 
The  imports  before  1914  were  in  large  part  from  Germany  and  aver- 
aged around  25,000  tons  annually.  In  1917  and  1918  there  were 
practically  no  imports. 

industrial  application  and  uses. 

The  principal  barium  products  are  ground  barytes,  barium  chemi- 
cals, and  lithopone.  Ground  barytes  is  used,  in  making  ready  mixed 
paints,  in  the  rubber  industry,  and  in  making  stiff  heavy  cardboards 
and  papers.  The  production  of  various  barium  salts  and  chemicals 
has  greatly  increased  in  the  last  few  years.  The  principal  chemicals 
are  barium  binoxide,  barium  carbonate,  barium  chloride,  barium 
nitrate,  and  barium  sulphate.  They  have  a  wide  variety  of  uses  and 
enter  into  the  manufacture  of  other  products.  Barium  binoxide  is 
used  in  the  manufacture  of  hydrogen  peroxide  and  in  the  preparation 
of  oxygen.  The  chloride  and  carbonate  are  used  in  the  preparation 
of  other  chemicals,  in  making  rat  poison,  as  a  water  softener,  and  in 
the  preparation  of  flat  wall  paints.  The  nitrate  is  used  in  explosives, 
fire  works,  signal  lights,  etc.  It  produces  'green  fire.'  The  chlorate 
is  also  used  in  pyrotechnics.  The  sulphate  is  extensively  used  in  the 
paint  industry,  and  also  in  making  paper,  putty,  and  rubber.  Litho- 
pone is  used  as  a  pigment  in  the  manufacture  of  wall  paints  and  rub- 
ber goods.  Minor  uses  are  in  the  preparation  of  enamel,  calcimine 
and  paper. 

Properties  and  ores. 

Barite  (BaSO^)  Barium  sulphate.  It  is  the  most  common  barium 
mineral.  Contains  65.7%  BaO  and  34.3%  SO3.  Called  heavy  spar 
because  of  its  weight  (specific  gravity  4.3-4.6).  Color  pure  white  to 
yellow  or  brown,  vitreous  luster,  sometimes  pearly,  cleavage  perfect 
basal  and  good  prismatic.  Hardness  2.5-3.5.  Occurs  massive  and 
granular  or  as  tabular  prismatic  crystals. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  21 

Witherite  (BaCO.,)  Barium  carbonate.  Contains  77.7%  BaO  and 
22.3%  CO2.  Color  white  to  gray  or  yellow,  transparent  or  translu- 
cent, luster  vitreous  or  slightly  resinous,  imperfect  cleavage.  Hardness 
3.0-3.7,  and  specific  gravity  4.3.     Occurs  massive,  granular  or  fibrous. 

Distribution. 

Barite  is  one  of  the  common  minerals  of  the  state.  It  is  a  common 
gangue  mineral  in  vein  deposits  and  is  especially  associated  with 
galena,  and  therefore  prominent  in  silver-lead  districts.  The  produc- 
ing properties  are  located  in  Mariposa  and  Monterey  counties,  and 
it  is  also  known  to  occur  in  Inyo,  Los  Angeles,  San  Bernardino  and 
Santa  Barbara  counties.  The  deposit  at  El  Portal  in  Mariposa  County 
lias  given  the  largest  commercial  production  to  date.  Witherite  is 
frequently  associated  with  barite,  but  usually  in  small  amounts.  The 
deposit  at  El  Portal  is  the  onl}^  one  of  record  in  the  United  States  from 
wliich  commercial  quantities  of  the  carbonate  have  been  shipped. 
Total  production  in  California  in  1918  was  100  tons  valued  at  $1500 
as  compared  with  4420  tons  valued  at  $25,633  in  1917. 

Of  the  states,  Georgia  and  ^Missouri  are  the  largest  producers,  al- 
though considerable  tonnage  is  produced  in  Tennessee,  Kentucky  and 
Alabama. 

Tests. 

The  barium  minerals  are  most  readily  distinguished  by  their  great 
weight.  They  give  a  yellowish-green  color  to  the  flame,  which  is 
intensified  by  moistening  the  mineral  with  hydrochloric  acid.  With 
the  exception  of  the  silicates,  barium  minerals  when  intensely  heated 
before  the  blowpipe  and  placed  on  moistened  turmeric  paper  will  turn 
it  red  (alkaline  reaction).  Barite  is  insoluble  in  water  or  acids,  while 
witherite  will  bubble  and  eifervesce  upon  the  application  of  hydro- 
chloric acid.  Witherite  may  be  readily  distinguished  from  strontianite, 
which  it  resembles,  by  the  flame  test. 

Preparation. 

In  the  preparation  of  ground  barytes,  the  crude  material  is  first 
crushed  to  about  one  inch  size,  and  then  washed  in  jigs  or  similar 
inachines  to  remove  the  clay,  calcite,  silica,  iron  oxide,  etc.  It  is  then 
ground  fine  and  bleached  by  treating  with  sulphuric  acid  for  8  to  12 
hours  in  lead-lined  tanks.  The  bleaching  process  is  a  very  important 
one,  as  the  product  must  have  a  perfectly  uniform  color.  After 
bleaching  it  is  washed  several  times  and  then  pulverized  to  pass  a 
200  or  300  mesh  screen,  and  in  some  cases  is  water  floated  to  insure 
a  uniformly  fine  product.     It  is  then  dried  and  packed. 


22  CALIFORNIA   STATE    MINING  BUREAU. 

Lithopone  is  a  mixture  of  about  70%  barium  sulphate,  25  to  29% 
zinc  sulphide  and  1  to  5%  zinc  oxide,  and  is  prepared  by  mixing  hot 
solutions  of  barium  sulphide  and  zinc  sulphate.  The  precipitate  is 
filtered,  dried  with  great  heat,  then  placed  in  water  and  ground  to  a 
pulp,  after  which  it  is  filtered,  dried  and  packed. 

BISMUTH. 

The  demand  for  bismuth,  owing  to  its  limited  use,  did  not  increase 
to  any  great  extent  during  the  war.  For  the  past  several  years  there 
have  been  only  two  producers  of  bismuth  in  this  country:  the  United 
Metals  Refining  Company  at  Grasseli,  Indiana,  and  the  American 
Smelting  and  Refining  Company  at  Omaha,  Nebraska.  The  bismuth 
produced  in  this  country  is  almost  entirely  a  by-product  obtained  in 
the  refining  of  lead  bullion. 

Bolivia  has  been  the  Avorld's  principal  producer,  in  recent  years. 
The  entire  consumption  in  this  country  is  probably  somew^hat  less  than 
250  short  tons  annually. 

The  price  for  the  metal  ranges  from  $3  to  $i  per  pound. 

The  only  commercial  production  recorded  in  California  was  from 
Riverside  County  in  1904,  when  20  tons  valued  at  $2400  were  pro- 
duced. Recovery  of  bismuth  in  the  electrolytic  refining  of  blister 
copper  has  been  reported,  ranging  as  high  as  27.3  pounds  of  metallic 
bismuth  per  100  tons  of  blister  copper  from  some  Shasta  County  ores. 

Industrial  application  and  uses. 

Bismuth,  because  of  its  low  melting  point  and  property  of  expanding 
when  cooling  from  a  molten  state,  is  used  principally  in  the  manufac- 
ture of  alloys.  Many  of  these  alloys  are  distinguished  by  having 
exceptionally  low  melting  points.  Metals  with  which  it  is  used  to  form 
alloys  are  copper,  tin,  lead,  and  antimony.  Such  alloys  are  used  in 
various  safety  devices  such  as  sprinkling  systems  for  fire  protection, 
safety  plugs  for  boilers,  electric  fuses,  etc.,  also  for  solders,  all  of 
which  uses  are  based  upon  the  low  melting  point.  Also  used  for 
type  and  bearing  metals. 

Considerable  bismuth  is  used  for  medicinal  purposes,  surgical  dress- 
ings, and  the  oxide  and  subnitrate  are  used  in  porcelain  painting  and 
glazing. 

Properties  and  ores. 

Bismuth  (Bi)  is  a  silver  white  metal  with  a  slight  reddish  tinge. 
Metallic  luster  which  does  not  tarnish  in  dry  air,  but  becomes  dull 
and  dark  brown  in  moist  air.  It  is  soft  (hardness  2.0-2.5),  quite 
heavy  (specific  gravity  9.70-9.83)   and  very  brittle.     When  heated  in 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  23 

the  air  it  burns  with  a  bluish  flame,  forming  a  yellowish  oxide.  Native 
bismuth  sometimes  occurs  with  its  ores  and  also  with  the  ores  of  cobalt 
silver  and  gold. 

Bismite  (BisOg)  Oxide  of  bismuth.  Bismuth  ocher.  Color  gray  to 
yellow.     Occurs  as  soft  earthy  coatings. 

Bismiitite  (BioCOsHgO)  Hydrous  carbonate  of  bismuth.  Color 
white  to  dirty  green.  Vitreous  to  dull  luster.  Occurs  as  incrusta- 
tions and  earthy. 

Bismuthinite  (Bi^Sg)  Sulphide  of  bismuth.  Bismuth  glance.  Lead 
gray  color  and  streak,  metallic  luster,  hardness  2.0,  specific  gravity 
C.4-6.5.  It  is  supposed  that  the  bismuth  occurring  in  gold  and  copper 
concentrates  is  in  this  form.  As  a  distinct  mineral  has  only  been 
noticed  in  a  few  localities. 

Distribution. 

Native  bismuth  and  the  ore  bismite  have  been  found  in  the  tour- 
maline gem  district  in  San  Diego  and  Riverside  counties,  and  several 
bismuth  minerals  have  been  found  in  small  quantities  in  Inyo,  Mono, 
Fresno.  Nevada,  San  Bernardino  and  Tuolumne  counties.  Native 
bismuth  is  often  found  in  pegmatitic  veins. 

Tests. 

Usually  bismuth  is  easily  reduced  from  its  compounds  by  mixing 
a  little  of  the  powdered  mineral  with  3  volumes  of  sodium  carbonate, 
and  heating  on  charcoal  in  the  reducing  flame  of  the  blowpipe.  The 
globules  of  the  metal  thus  obtained  are  bright  when  hot  and  dull  when 
cold,  brittle  and  easily  fusible.  The  charcoal  is  covered  with  a  coating 
of  bismuth  oxide  which  is  a  lemon  to  orange  yellow  color  near  the 
assay  and  white  a  little  distance  away. 

When  heated  on  charcoal  in  small  oxidizing  flame  with  3  or  4  vol- 
umes of  a  mixture  of  potassium  iodide  and  sulphur,  a  coating  is 
produced  Avhich  is  yellow  near  the  a^say,  and  bordered  on  the  outer 
edge  with  brilliant  red. 

If  the  mineral  is  soluble  in  hydrochloric  acid,  evaporate  the 
solution  until  only  a  few  drops  remain  and  then  pour  into  a  test  tube 
about  one-third  full  of  water.     A  white  precipitate  will  form. 

Metallurgy. 

The  metallurgy  of  bismuth  is  similar  to  that  of  lead,  and  as  stated 
above,  almost  all  the  bismuth  produced  in  the  United  States  is  obtained 
in  the  electrolytic  refining  of  lead  bullion.  The  greatest  part  of  the 
world  production  comes  from  Bolivia  in  the  form  of  crude  bullion 
and  is  sent  to  London,  England,  for  refining.     The  refining  of  bismuth 


24  CALIFORNIA   STATE   MINING  BUREAU. 

base  bullion  requires  great  skill,  the  value  of  the  refined  metal  de- 
pending upon  the  method  and  care  with  which  it  is  refined.  There 
are  only  a  few  specialists  in  this  line. 

BORAX. 

California  is  the  sole  producer  of  borax  in  the  United  States.  The 
existence  of  deposits  in  western  Nevada  has  been  known  for  years, 
and  considerable  exploration  has  recently  been  made,  notably  at  Cave 
Springs. 

Production  consists  principally  of  the  mineral  colemanite  mined 
in  Inyo  and  Los  Angeles  counties. 

Industrial  application  and  uses. 

The  principal  compounds  derived  from  the  crude  borate  minerals 
are  borax  and  boric  acid.  Of  these  two,  borax  is  produced  in  larger 
quantities.  The  greater  part  consumed  in  this  country  is  used  in 
the  manufacture  of  enamel  or  porcelain  coatings  for  cooking  utensils, 
sinks,  bathtubs,  etc.  About  one-quarter  of  the  total  production  of 
both  borax  and  boric  acid  is  sold  through  the  wholesale  and  retail 
druggists,  and  other  dealers  for  domestic  reqairements.  About  one- 
third  of  the  combined  production  is  used  in  the  manufacture  of  other 
chemicals.  The  remainder  is  accounted  for  in  its  use  among  fish  and 
meat  packers,  tanners  and  manufacturers  of  glass,  soap  and  pottery. 

Properties  and  ores. 

Borax  is  a  hydrous  borate  of  sodium  (NaoB^O^lOHgO).  It  is 
colorless  or  white,  sometimes  transparent,  dull  to  greasy  luster,  very 
soft  (hardness  2.0-2.5)  and  light  (specific  gravity  1.7).  Has  a  sweet 
and  alkaline  taste.  Occurs  as  a  powder,  incrustations,  or  small  crj^s- 
tals.  Contains  approximately  36.5%  B^Og,  16.5%  Na20  and  47% 
H,0. 

Colemanite  is  a  hydrous  borate  of  calcium  (CagBcOn  SHoO).  Color- 
less, Avhite,  or  yellow  white,  vitreous  luster,  hardness  4.0-4.5,  specific 
gravity  2.4.  Occurs  in  beds,  interstratified  with  lake  sediments,  as 
clays,  sandstones  and  conglomerates.  Contains  approximately  50% 
B2O3,  27.5%  CaO  and  22.5%  HoO. 

Ulexite,  called  'cotton  balls.'  Hydrous  borate  of  sodium  and 
calcium  (NaCaBjjOo.SHgO).  Color  white,  silky  luster,  very  soft, 
and  light.     Usually  in  nodules  or  sheets  of  fine  fibers. 

Distribution. 

Borax  was  first  discovered  in  California  in  the  waters  of  Tuscan 
Springs  in  Tehama  County  in  1856.     Later  in  the  same  year  Borax 


COMMERCIAL   MINERALS  OF   CAUFORNIA.  25 

Lake  in  Lake  County  was  discovered.  This  latter  deposit  produced 
over  one  million  pounds  of  refined  borax  from  1864  to  1868.  This  was 
the  first  commercial  output  in  the  United  States.  Production  from 
the  dry  lake  deposits  in  Inyo  and  San  Bernardino  counties  began  in 
1873  and  in  1887  the  industrj^  was  revolutionized  by  the  discovery 
of  colemanite  beds  at  Calico  in  San  Bernardino  County,  These  have 
since  been  worked  out,  and  the  present  production  comes  from  similar 
beds  in  Inyo  and  Los  Angeles  counties.  There  are  colemanite  de- 
posits in  Ventura  Count}^  that  have  not  been  worked  on  account  of 
no  transportation  facilities.  The  natural  borax  is  usually  accompanied 
by  sulphates  of  lime  and  soda  and  is  common  at  many  depressions 
or  sinks  in  the  desert. 

Tests. 

Easily  distinguished  by  its  physical  properties  and  taste.  "When 
heated  it  fuses  easily  with  much  swelling  and  imparts  a  yellow  color 
to  the  flame.  It  is  readily  soluble  in  water  and  dilute  hydrochloric 
acid.  Turmeric  paper,  when  moistened  with  the  solution  and  dried, 
assumes  a  reddish-brown  color.  Most  borates  impart  a  green  color 
to  the  blowpipe  flame. 

Preparation. 

Colemanite  is  washed  to  remove  soluble  sulphates  and  chlorides, 
and  then  boiled  with  a  slight  excess  of  sodium  carbonates.  The  clear 
liquid 'is  allowed  to  crystallize,  producing  a  crude  borax,  containing 
some  Glauber  salt  (NasSO^.lOIIoO).  This  is  redissolved,  heated,  a 
little  sodium  hypochlorite  added,  and  the  liquid  run  into  closed 
crystallizing  tanks,  where  it  cools  very  slowl}^  When  the  tempera- 
ture reaches  33°  C.  the  mother  liquid  is  drawn  off,  leaving  the  pure 
crystallized  borax. 

CADMIUM. 

Cadmium  was  first  produced  in  the  United  States  in  1907  by  a  single 
chemical  company  and  the  industry  has  grown  until  in  1917  there 
were  six  producing  companies,  one  of  which  was  located  in  California. 

Previous  to  this  production,  the  greatest  output  came  from  the  zinc 
producing  regions  of  Silesia,  where  it  was  recovered  as  a  by-product 
in  the  distillation  of  the  zinc.  In  1907  the  domestic  production  was 
nearly  sufficient  to  supply  tbe  home  demand,  but  in  the  next  few  years 
the  imports  increased.  Since  1912,  however,  the  home  production  has 
made  great  strides  and  in  the  last  four  years  the  imports,  which  came 
largely  from  Germany,  have  been  practically  stopped. 

The  domestic  supply  is  derived  from  plants  wliieh  treat  zinc  ores, 
or  lead  ores  carrying  zinc. 


26  CALIFORNIA   STATE    MINING  BUREAU. 

Production  was  recorded  in  California  for  the  first  time  in  1917. 
This  was  several  thousand  pounds  of  metallic  cadmium,  but  exact 
figures  cannot  be  given  because  the  output  was  by  a  single  company. 

Industrial  application  and  uses. 

Cadmium  is  used  principally  in  the  so-called  cliche  alloys.  These 
alloys  have  an  exceedingly  low  melting  point  and  are  said  to  be  supe- 
rior to  those  of  bismuth.  They  are  used  mostly  in  safety  plugs  for 
boilers,  electrical  apparatus,  automatic  sprinkler  systems,  etc.  Re- 
cently it  has  been  used  as  a  substitute  for  tin  in  solders.  It  is 
believed  to  have  a  certain  military  use  in  smoke  bombs,  and  small-arms 
ammunition. 

Various  cadmium  salts  are  used  in  medicines,  dentistry,  dyeing, 
photography  and  electroplating. 

Properties  and  ores. 

Cadmium  is  produced  in  two  forms :  metallic  cadmium  and  the 
pigment  cadmium  sulphide.     Metallic  cadmium  rarely  occurs  in  nature. 

It  is  white,  lustrous,  rather  soft,  and  has  a  very  low  melting  point, 
and  specific  gravity  of  8.6. 

GreenocJcite  (CdS),  cadmium  sulphide  is  the  only  cadmium  mineral 
and  is  very  rare.  It  is  lemon  or  orange  yellow  in  color,  resinous  or 
adamantine  luster,  hardness  3.0-3.5,  specific  gravity  4.9-5.0.  Occurs 
as  thin  coatings  on  sphalerite. 

Distribution. 

In  California  cadmium  has  been  produced  at  the  electrolytic  zinc 
plant  of  the  Mammoth  Copper  Company,  in  Shasta  County.  It  occurs 
associated  with  the  zinc  sulphide,  sphalerite,  probably  as  greenockite. 
Occurrences  have   also  been  noted  in  Mono   and  Riverside  counties. 

Tests. 

The  sulphide  greenockite,  when  heated  on  charcoal  in  the  reducing;' 
flame  of  the  blowpipe  with  a  little  sodium  carbonate,  gives  a  reddish- 
brown  coating  of  cadmium  oxide.  To  distinguish  from  zinc,  with 
which  it  usually  occurs,  the  cadmium  coating  occurs  before  that  of 
zinc.  Also  when  treated  with  warm  hydrochloric  acid,  hydrogen 
sulphide  gas  is  given  off  which  may  be  distinguished  by  its  odor. 

CEMENT  AND   LIME. 

Cement  is  one  of  the  most  valuable  mineral  products  of  the  state, 
ranking  fourth  in  value  in  1918.  The  recent  increased  demand  for 
this  material  in  many  branches  of  the  great  war  construction  program 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  27 

has  been  greatl}'  felt  in  California,  as  well  as  in  the  other  producing 
states. 

Portland  cement  was  first  produced  commercially  in  California  in 
1891.  and  the  industry  has  advanced  in  rapid  strides  since  then. 

Industrial  application  and  uses. 

Cement  is  one  of  the  most  important  structural  materials.  In  con- 
crete and  reinforced  concrete  buildings,  bridges,  docks  and  structures 
of  all  kinds,  concrete  road-beds,  pavements,  water  pipes,  sewers,  etc., 
enormous  quantities  are  used.  Under  war  conditions  structural  steel 
is  expensive,  difficult  to  obtain  and  greatly  needed  for  military  pur- 
poses, and  every  effort  has  been  made  to  substitute  reinforced  concrete 
wherever  possible.  The  construction  of  concrete  ships  which  has  re- 
cently become  a  great  success,  and  other  industries  which  this  will 
liO  doubt  lead  to,  will  call  for  a  considerable  increase  in  the  output  of 
cement. 

Lime  is  most  commonly  used  in  the  form  of  'slaked  lime'  in  mortar 
and  whitewash.  It  is  also  used  in  making  bleaching  powder,  calcium 
carbide,  sodium  hydroxide,  in  glass  manufacture,  to  remove  hair  from 
hides,  in  dyeing  and  bleaching  cloth,  and  as  a  disinfectant. 

Limestone  is  used  as  a  smelter  flux,  as  a  purifier  in  the  sugar 
industr^^,  as  a  fertilizer,  for  various  roofing  preparations,  paints,  etc., 
and  for  making  carbon  dioxide. 

Properties  and  ores. 

Limestone  (CaCOg),  calcium  carbonate,  in  its  many  varieties,  is 
one  of  the  most  common  minerals,  and  vast  deposits  are  found  in 
many  states.  The  common  varieties,  having  the  same  composition, 
are  ealcite,  marble,  Iceland  spar,  onyx,  chalk,  coral,  stalactites,  stalag- 
mites, travertine,  etc.  The  large  deposits  are  massive  or  granular, 
while  perfect  rhombohedral  crystals  of  ealcite  are  very  common.  The 
color  is  white,  yellow,  brown,  pink,  or  bluish;  vitreous  luster;  soft 
(hardness  3.0);  specific  gravity  2.7;  perfect  cleavage. 

Lime  (CaO),  calcium  oxide  is  a  hard  white  solid,  formed  by  heating 
limestone  in  partly  closed  containers.  When  exposed  to  the  air  it 
becomes  'air  slaked,'  i.e.,  absorbs  water  and  carbon  dioxide,  swells 
and  crumbles  to  a  powder.  It  combines  actively  wuth  water,  giving 
off  considerable  heat,  as  may  be  seen  in  the  preparation  of  mortar. 
The  product  is  called  'slaked  lime.'  Pure  lime  is  almost  infusible, 
and  when  heated  intensely  gives  off  a  brilliant  white  light. 

Cement  is  made  by  heating  to  an  incipient  fusion  a  mixture  of  lime- 
stone and  clay  and  grinding  the  clinker  product  to  a  fine  powder.  It 
must  meet   certain  standard  specifications  such  as  fineness,  specific 


28  CALIFORNIA   STATE   MINING  BUREAU. 

gravity,  loss  on  ignition,  etc.,  and  when  mixed  with  water  must  develop 
a  required  tensile  strength  when  it  'sets.'  When  mixed  with  sand, 
gravel,  or  crushed  rock  and  water,  the  product  is  concrete,  and  when 
reinforced  with  steel  rods  or  bars,  it  becomes  reinforced  concrete.        , 

Distribution. 

In  San  Bernardino  County  there  were  three  operating  cement  plants 
in  1918.  The  following  counties  each  have  one  plant  in  operation: 
Contra  Costa,  Kern,  Napa,  Riverside,  Santa  Cruz  and  Solano.  Lime 
was  produced  principally  in  Santa  Cruz  and  San  Bernardino  counties. 

Pennsylvania  is  the  largest  cement  producer,  followed  by  Indiana, 
New  York,  California,  Missouri,  Michigan,  Kansas  and  Iowa. 

Tests. 

Fragments  of  caleite,  or  limestone,  when  treated  with  cold  dilute 
hydrochloric  acid  effervesce  freely.  If  a  small  amount  of  the  powdered 
mineral  is  dissolved  in  a  very  small  quantity  of  hydrochloric  acid  and 
then  dilute  sulphuric  acid  added,  a  white  precipitate  of  calcium 
sulphate  will  be  formed. 

CHALK. 

Chalk  is  a  v^ariety  of  limestone,  made  up  of  small  and  generally 
broken  or  powdered  shells  of  marine  mollusks,  a  large  proportion  of 
which  are  microscopic  forms  called  foraminifera.  It  is  white,  very 
light  and  loosely  coherent  in  structure. 

It  is  quite  common  in  parts  of  Europe  and  the  most  noteworthy 
deposits  are  in  the  high  cliffs  along  the  English  coast  near  Dover. 

True  chalk  was  not»  found  in  the  United  States  until  recent  years. 
The  material  used  was  imported  from  Hull,  England.  Deposits  of 
considerable  extent  are  now  known  to  exist  in  Arkansas,  Kansas,  New 
Mexico  and  Texas,  and  some  commercial  production  has  been  made. 
No  deposits  have  been  found  in  California,  but  the  limestone  produced 
in  this  state  is  used  for  purposes  similar  to  those  for  which  chalk  is 
utilized.     (See  Lime  and  Cement.) 

Infusorial  and  diatomaceous  earth  are  chalk-like  materials,  but 
are  composed  of  pure  silica,  and  are  sometimes  incorrectly  spoken  of 
as  chalk.     These  materials  are  described  under  that  heading. 

CHROMIUM. 

The  war  demand  for  chrome  ore  increased  activities  in  this  branch 

of  the  mining  industry  to  an  enormous  extent.     California  is  by  far 

the  greatest  producer  in  the  United  States — in  fact,  before  1916  it 

was  for  many  years  the  sole  producer,  and  the  great  increase  in  the 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  29 

domestic   supply   after  the  United   States  entered   the  war  was  due 
almost  entirely  to  the  increased  output  in  California. 

Owing  to  the  fact  that  the  characteristic  occurrence  of  high  grade 
chromite  is  in  the  form  of  comparatively  small  kidney-shaped  masses 
in  serpentine,  it  is  difficult  to  make  an  estimate  of  the  amount  of  ore 
in  a  deposit,  and  ore-bodies  cannot  be  blocked  out  and  future  operations 
calculated  as  in  the  case  of  other  important  minerals. 

Industrial  application  and  uses. 

Chromite  is  used  most  extensively  as  a  refractory-lining  in  furnaces 
for  smelting  steel  and  copper.  Large  amounts  also  are  used  in  making 
chrome-steel  alloys,  which  go  into  the  manufacture  of  armor  plate, 
projectiles,  aeroplane  motors,  automobiles,  etc.  Chemicals  for  dyes, 
paints  and  leather  tanning  are  also  made  from  this  ore. 

Properties  and  ores. 

Chromium  never  occurs  free  in  nature.  Its  chief  ore  is  the  oxide 
called  chromite,  or  chrome  iron  (FeCrgO^).  It  is  iron  black  in  color, 
powders  brown,  has  a  brown  streak  and  sub-metallic  luster.  Breaks 
with  a  rough  unpolished  surface.  It  is  very  heavy  (specific  gravity 
-4.5)  and  quite  hard  and  tough.  Usually  found  in  masses  in  green 
serpentine,  or  along  the  contacts  betw^een  serpentine  and  slate  or  other 
similar  rocks.  It  is  one  of  the  primary  minerals  in  deep-seated 
igneous  rocks,  rich  in  iron  and  magnesia,  sucli  as  peridotite  and  p}'- 
roxenite.  The  associated  minerals,  olivine  and  pyroxene,  are  altered 
to  serpentine,  so  that  it  is  recognized  as  the  enclosing  rock  of  mast 
bodies  of  chromite. 

Distribution. 

Information  gathered  by  the  Mining  Bureau  shows  there  is  quite  a 
distinct  belt  of  deposits  extending  along  the  foothills  of  the  Sierra 
Nevada  from  the  vicinity  of  Quincy,  southerly,  through  the  central 
portion  of  Nevada  and  Placer  counties,  and  the  western  portion  of 
El  Dorado,  Amador,  Calaveras  and  Tuolumne  counties.  There  have 
been  no  deposits  reported  from  Madera  County,  but  there  seems  to 
be  an  extension  of  the  above  belt  through  Fresno  County  a  few  miles 
east  of  Fresno,  and  through  Tulare  County  from  Visalia  southerly 
to  the  vicinity  of  Porterville. 

There  is  a  belt  of  scattered  deposits  in  the  Coast  Range  in  Napa, 
Sonoma,  Lake  and  Mendocino  counties.  Quite  a  distinct  belt  extends 
nort"herly  and  southerly  through  the  central  easterly  portion  of  Butte 
County.     In  the  north  a  belt  extends  through  the  central  portion  of 


30  C^VLIFORNIA   STATE    MINING  BUREAU. 

Siskiyou  County,  southerly  into  the  northwesterly  portion  of  Shasta 
County.  There  are  many  other  deposits,  notabl}^  in  Del  Norte,  Te- 
hama, Glenn,  Alameda,  Inyo,  San  Luis  Obispo,  Santa  Clara,  and 
Stanislaus  counties. 

Test. 

An  easy  test  for  this  mineral  may  be.  made  with  the  borax  bead,  or 
soda  phosphate  bead,  made  by  dipping  a  small  loop  of  fine  platinum 
wire  in  borax  or  soda  phosphate,  and  heating  until  reduced  to  a  clear 
glass.  A  very  small  portion,  or  a  little  of  the  powder  of  the  mineral 
containing  chromium,  will  color  this  bead  a  beautiful  green. 

Metallurgy. 

Chromite  containing  around  40%  CrgOg  is  made  into  bricks  slightly 
larger  than  the  ordinary  building  bricks  and  used  directly  as  a  re- 
fractory lining. 

Ferro-Chromium,  used  in  the  manufacture  of  steel,  is  made  in  the 
electric  furnace.  The  finely  ground  chromite  is  mixed  with  coal  and 
shoveled  into  the  furnace  around  the  electrodes.  Reduction  takes 
place  and  the  alloy  is  tapped  from  the  bottom  of  the  furnace  into  iron 
receivers.  The  charging  is  continuous  so  that  the  top  of  the  mix 
remains  unfused. 

The  alloy  contains  from  60  to  65%  chromium  and  from  5  to  9% 
carbon.  For  the  higher  grade  ferro-chromiums,  a  subsequent  refining 
is  necessary.  The  physical  properties  depend  upon  the  amount  of  car- 
bon present.  When  containing  5%  or  more  carbon,  the  alloy  is  iron 
gray  in  color,  when  containing  2.5%  carbon  it  resembles  aluminum, 
and  with  0.5%  carbon  it  is  much  like  pure  lead.  Chromite  containing 
about  50%  Cr203  is  the  ore  generally  used  for  the  production  of 
ferro-chromium. 

Low  grade  ores  have  been  successfully  concentrated  by  both  the 
ordinary  wet  and  dry  methods  of  concentration. 

The  chromium  steels  contain  from  0.5%  to  4%  chromium,  and  from 
0.2%  to  slightly  over  1%  carbon.  Armor  plate  steel  contains  about 
1.5%  chromium,  3.25%  nickel  and  0.25%  carbon. 

In  the  manufacture  of  steel,  chromium  does  not  remove  impurities 
as  to  titanium,  manganese  and  silicon.  In  small  amounts,  it  increased 
the  tensil  strength  and  hardness  without  decreasing  its  ductility,  but 
in  large  amounts  it  causes  brittleness. 


COMMERCIAL   MINERALS   OF   CAIJFORNIA.  31 

CLAY,  POTTERY,  BRICK  AND  TILE. 

Ohio  has  for  many  years  been  the  leading  state  in  the  value  of 
clay  products,  followed  by  Pennsylvania,  New  Jersey  and  Illinois. 

Industrial  application  and  uses. 

Common  brick  has  for  years  been  one  of  California's  principal  pro- 
ducts and  is  extensively  used  in  building  construction.  Building  tile 
is  also  largely  used  in  many  kinds  of  structural  work.  Clay  when 
made  into  pottery  is  used  for  sewer  pipe,  chimney  pipe,  architectural 
terra  cotta,  ornamental  tiling,  porcelain,  sanitary  ware,  stoneware, 
flower  pots,  etc.  Sewer  pipe  is  the  most  valuable  product,  with 
architectural  terra  cotta  and  sanitary  ware  ranking  next. 

Properties. 

The  clays,  in  general,  are  aggregates  of  hydrous  and  anhydrous 
aluminous  silicates,  free  silica  and  varying  quantities  of  iron  oxides, 
with  calcium  and  magnesian  carbonates.  They  are  of  secondary  origin, 
resulting  from  the  decomposition  of  various  rocks  and  minerals,  and 
the  accumulation  of  their  less  soluble  residues.  Most  of  the  common 
clay  or  kaolin  results  from  the  decomposition  of  feldspar. 

The  most  striking  characteristics  of  clays  are  their  plasticity,  i.  e., 
easily  molded  into  various  shapes,  and  their  induration,  i.  e.,  become 
hard  and  resistant  upon  heating.  They  are  moistened  with  water  and 
molded  into  various  shapes  by  hand  on  the  potters  wheel,  or  shaped 
by  molds  or  presses.  When  dried  and  burned  in  a  kiln  they  become 
Arm  and  hard  like  stone,  entirely  lose  their  plastic  property  and 
are  very  resistant  to  the  action  of  water,  air  and  heat. 

In  color  they  may  be  white,  yellow,  brown,  blue  or  red. 

Distribution.  • 

Pottery  clay  is  very  widely  distributed  in  California,  having  been 
produced  at  various  times  in  thirty-three  counties.  In  1917  the 
largest  producing  counties  were,  in  order.  Riverside,  Amador,  Placer, 
Los  Angeles,  Alameda,  and  Santa  Clara.  There  are  many  large  pot- 
tery works  which  produce  a  great  variety  of  products,  including  many 
architectural  and  ornamental  shapes.  In  the  manufacture  of  brick, 
Los  Angeles  County  leads  all  others  by  a  large  margin,  followed  by 
Alameda,  Contra  Costa  and  Riverside  counties. 

Tests. 

To  be  of  the  most  commercial  value,  clay  should  be  extremely  plastic, 
should  be  free  from  coarse  sand  or  other  coarse  material  and  should 
be  low  in  iron  if  a  ligrht  colored  ware  is  desired. 


32  CALIFORNIA   STATE    MINING   BUREAU. 

COAL. 

As  early  as  1860  coal  was  produced  in  California  and  in  1861 
there  was  a  reported  production  of  6,620  short  tons.  During  the  next 
forty  odd  years  there  were  several  coal  mines  of  considerable  size  in 
operation^  which  contributed  substantial!}^  to  the  fuel  of  the  state, 
the  production  reaching  a  maximum  in  1880  of  236,950  short  tons. 
Of  more  recent  years  the  greatest  production  of  record  was  in  1900 
when  176,956  tons  were  produced,  valued  at  $535,531. 

The  development  of  the  petroleum  industry  in  California  has  forced 
coal  into  the  background.  Since  1903,  the  production  has  rapidly 
fallen  off  and  now  the  coal  mines,  with  a  few  exceptions,  are  practi- 
cally abandoned. 

q 
Properties. 

In  general,  the  California  coal  as  mined,  is  of  an  inferior  quality, 
being  soft,  friable  and  lignitic.  It  disintegrates  soon  after  mining 
and  will  not  stand  much  handling.  This  has  made  it  difficult  for 
producers  to  compete  with  coal  of  better  quality  from  outside  sources. 

Distribution. 

The  principal  coal  producing  districts  in  California  have  been  as 
follows;  north  of  Mount  Diablo  in  Contra  Costa  County;  at  Corral 
Hollow  near  Tesla,  several  miles  to  the  southeast  in  Alameda  County; 
Stone  Canyon  in  Monterey  County ;  and  near  lone  in  Amador  County. 

In  the  district  north  of  Mount  Diablo  there  are  two  principal  beds, 
each  having  a  thickness  of  about  three  feet,  with  other  small  beds, 
only  a  few  inches  in  thickness.  Although  the  district  is  much  faulted, 
coal  outcrops  can  be  traced  on  the  surface  for  several  miles.  These 
deposits  were  first  worked  in  1861.  They  belong  to  the  Upper  Cret- 
aceous or  Lower  Eocene  period  and  occur  ifi  light  colored  sandstones 
and  associated  shales. 

The  deposits  at  Corral  Hollow  or  Tesla,  in  Alameda  County,  are 
along  the  same  general  strike  and  of  the  same  geological  period  as 
those  north  of  Mount  Diablo.  The  beds  are  narrow  and  much  faulted. 
They  were  discovered  in  1870  and  are  said  to  be  not  yet  worked  out. 

Deposits  in  the  Stone  Canyon  district  were  discovered  in  1870,  but 
were  not  worked  until  1908.  These  mines  are  located  on  the  west  side 
of  the  Mount  Diablo  range,  twenty-three  miles  northeast  of  Bradley, 
Monterey  County.  The  coal  bed  has  a  uniform  thickness  of  about 
fifteen  feet,  and  is  said  to  extend  for  eight  miles.  The  coal  is  bitu- 
minous and  of  a  better  quality  than  that  from  the  other  districts. 

The  production  is  reported  to  have  been  in  the  neighborhood  of 
27,000  tons  in  1909. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  33 

111  the  lone  district,  Amador  County,  thirty-six  miles  southeast  of 
Sacramento,  the  coal  beds  vary  from  five  to  fifteen  feet  in  thickness. 
They  are  lignite,  near  the  surface  and  easily  worked.  The  district 
has  been  a-  small  but  continuous  producer  since  1877  and  the  coal  has 
found  a  ready  local  market. 

In  Rivei-side  County,  six  miles  east  of  Elsinore,  coal  has  been  mined 
from  a  small  deposit  for  a  number  of  years.  It  is  lignite,  and  is  used 
locally  for  heating  purposes.  Other  workable  deposits  are  known  to 
exist  in  Fresno,  Mendocino,  Shasta,  Siskiyou  and  San  Benito  counties. 

The  Beckman-Linden  Engineering  Corporation,  593  Market  street, 
San  Francisco,  in  June,  1919,  purchased  the  Tesla  property  and  com- 
menced the  erection  of  buildings  and  the  installation  of  machinery 
and  equipment  for  mining  and  grinding  the  coal.  The  powdered 
product  will  be  used  at  the  property  for  the  generation  of  electric 
power.  It  will  be  fed  into  the  fire  boxes  of  boilers  by  air  blasts, 
similar  to  the  way  in  which  crude  oil  is  used.  This  method  has 
proved  highly  satisfactory  in  other  localities. 

Extensive  operations  are  planned  so  that  the  near  future  will  no 
doubt  witness  the  return  of  the  old  time  activities  in  this  district. 

COPPER. 

Copper  has  for  several  years  been  one  of  the  three  principal  mineral 
products  of  the  state,  being  exceeded  in  value  only  by  petroleum  and 
gold. 

It  is  one  of  the  stable  mineral  products  of  the  United  States,  rank- 
ing next  to  iron  in  usefulness.  The  main  producing  states  are  Ari- 
zona, Michigan,  Utah,  California,  Montana  and  Colorado. 

Its  many  and  varied  uses  have  constantly  increased  the  demand 
for  this  metal. 

Industrial  application  and  uses. 

Probably  the  greatest  single  use  for  copper  is  in  making  wire,  used 
for  telegraph  and  telephone  lines,  electric  railway  and  lighting  systems, 
cables,  and  electrical  apparatus  in  general.  In  the  form  of  sheets, 
foil,  bars,  wire,  bolts,  rivets,  washers,  etc.,  it  has  innumerable  uses  in 
almost  every  manufacturing  industry.  Many  household  articles,  cook- 
ing utensils,  boilers,  etc.,  are  made  of  copper.  All  nations  use  it  as 
the  chief  ingredient  of  small  coins.  Copper  plates  are  used  for  en- 
graving and  printing.  Many  alloys  are  composed  mainly  of  this  metal, 
brass  containing  from  63  to  72%,  the  remainder  being  zinc.  Brass 
is  harder  than  copper  and  has  many  uses  for  which  the  latter  is  not 
suited.  Bronze  contains  from  70  to  95%  of  copper.  Other  alloys 
are  gun  metal,  bell  metal  and  so-called  German  silver. 

3-24W 


34  CALIFORNIA   STATE   MINING  BUREAU. 

Properties  and  ores. 

Native  copper  (Cu)  has  the  well  known  copper-red  color,  metallic 
luster,  is  malleable  and  ductile,  soft  (hardness  2.5-3.0)  and  heavy 
(specific  gravity  8.83).  Found  in  irregular  masses,  wires  or  thin 
sheets,  cr.ystals  are  rare.  Ores  are  chalcocite,  ehalcopyrite,  bornite, 
tetrahedrite,  cuprite,  malachite  and  azurite. 

Chalcocite  (CugS)  Copper  sulphide.  Copper  glance.  Dark  lead-gray 
to  black  in  color,  black  streak,  metallic  luster,  hardness  2.5-3.0,  spec- 
ific gravity  5.7.  Generally  occurs  massive.  Contains  79.8%  copper 
and  20.2%  sulphur. 

Chalcopyrite  (CuFeS)  Copper  and  iron  sulphide.  Copper  pyrites. 
Color  deep  brass  yellow,  often  with  iridescent  tarnish,  streak  greenish 
black,  metallic  luster,  hardness  3.5-4.0,  specific  gravity  4.1-4.3.  Gen- 
erally ma^ssive.  Contains  34.6%  copper,  30.5%  iron  and  34.9% 
sulphur. 

Bornite  (CUgFeSg)  Copper  and  iron  sulphide.  Peacock  ore.  Color 
reddish-brown,  tarnished  to  peacock  colors,  grayish-black  streak,  metal- 
lic luster,  hardness  3.0,  specific  gravity  4.9-5.4.  Generally  massive. 
Contains  55.58%  copper,  16.36%  iron  and  28.6%o  sulphur. 

Cuprite  {Qu^O)  Red  oxide  of  copper.  Color  red,  streak  brownish- 
red,  submetallic  to  adamantine  luster,  hardness  3.5-4.0,  specific  gravity 
5.99.     Occurs  massive  and  contains  88.8%  copper  and  11.2%  oxygen. 

Tetrahedrite  (CugSbgSj)  Sulphantimonite  of  copper.  Gray  copper. 
Color  dark  steel  gray,  streak  black,  brown,  to  cherry-red,  metallic  lus- 
ter, hardness  3.0-4.5,  specific  gravity  4.4r-5.1.  Occurs  massive  and 
often  contains  iron,  zinc,  silver,  mercurj^  and  arsenic. 

Malachite  (CuCOsCuOH)  Basic  carbonate  of  copper.  Color  and 
streak  light  green,  vitreous  luster,  hardness  3.5-4.0,  specific  gravity 
4.0.     Structure  fibrous,  stalactitic,  botryoidal  or  radiating  tufts. 

Azurite  (2CuCOoCu(OH)2)  Color  deep  azure  blue,  streak  light 
blue,  vitreous  to  adamantine  luster,  hardness  3.5-4.0,  specific  gravity 
3.77-3.83,  occurs  massive,  earthy  or  in  good  crystal  aggregates.  * 

Distribution. 

By  far  the  greatest  production  in  California  comes  from  Shasta 
County.  In  1918  it  produced  25,294,590  pounds,  valued  at  $6,247,764. 
Production  was  reported  from  25  other  counties,  the  principal  ones 
being,  in  order,  Plumas,  Calaveras,  San  Bernardino,  Placer,  Siskiyou, 
Inyo  and  Madera. 

Tests. 

Copper  minerals  when  moistened  with  hydrochloric  acid  and  heated 
give  a  strong  azure-blue  color  to  the  flame,  which  is  usually  tinged  on 


COMMERCIAL    MINERALS   OF    CALIFORNIA.  35 

•  the  edges  with  emerald  green,  characteristic  of  copper  oxide.  The 
dilute  nitric  acid  solution  is  rendered  blue  by  the  addition  of  ammonia 
in  excess.  When  fused  before  the  blowpipe  on  charcoal  with  a  flux 
of  equal  parts  of  sodium  carbonate  and  borax,  metallic  globules  of 
copper  are  obtained. 

'     Metallurgy. 

Copper  ores  are  smelted  in  both  blast  and  reverberatory  furnaces. 
Iron  oxide,  limestone  and  silica  are  used  as  fluxes  and  coke  is  the  fuel 
commonly  used  in  blast  furnaces,  while  various  cheaper  fuels  may  be 
used  in  reverberatory  furnaces. 

In  the  blast  furnace  the  charge  is  introduced  through  a  door  at 
the  top  and  consists  of  alternate  layers  of  coke  and  ore,  the  latter 
being  mixed  with  fluxing  materials.  The  proper  proportion  of  fluxing 
materials  is  calculated  from  the  composition  of  the  particular  ore  to 
be  treated.  Combustion  is  maintained  by  blasts  of  hot  air  through 
openings,  called  'tuyeres'  near  the  bottom  of  the  furnace. 

As  the  charge  is  melted  to  a  fluid  condition,  the  metals  settle  to 
the  bottom  of  the  furnace  and  are  drawn  off  in  the  form  of  'matte.' 
This  is  a  mixture  of  sulphides,  principally  copper  and  iron,  and 
generally  contains  gold  and  silver  values.  The  fluxes  combined  with 
tlie  gangue  minerals  to  form  'slag'  which  remains  above  the  'matte,' 
and  is  drawn  off  at  intervals.  The  process  is  a  continuous  one.  new 
charges  being  added  at  regular  intervals. 

In  some  sulphide  ores  containing  a  high  percentage  of  sulphur  a 
preliminary  roasting  process  is  necessary  to  eliminate  some  of  the 
sulphur. 

In  the  reverberatory  furnace  the  fire  box  is  separated  from  the 
charge  by  a  low  partition  and  the  heat  is  carried  directly  over  the 
surface  of  the  mixed  ore  and  flux  by  a  draught.  This  furnace  is 
particularly  adapted  for  smelting  fine  ore  and  is  used  in  localities 
where  fuel  is  cheap.  The  capacity  is  not  usually  as  great  as  that  of 
the  blast  furnace  and  the  removal  of  the  'matte'  and  'slag'  and 
recharging  operations  necessitate  delays. 

The  molten  'matte'  resulting  from  either  of  the  above  smelting 
methods,  is  drawn  off  into  steel  ladels  and  transferred,  generally  by 
means  of  electric  cranes  to  the  converters.  These  converters  are  steel, 
bowl  shape  vessels  from  ten  to  twenty  feet  in  diameter  and  mounted 
so  that  they  may  be  tipped  to  receive  the  'matte'  or  to  discharge 
the  finished  product.  By  means  of  air  blasts,  through  'tuyers'  at  the 
bottom  of  the  converters,  the  charge  of  'matte'  is  oxidized  to  'blister 
copper'  which  contains  about  75%  copper.  Blister  copper  may  also 
be  produced  from  the  matte  by  a  series  of  roasting  operations  in 
reverberator}^  furnaces. 


36  CALIFORNIA   STATE   MINING  BUREAU. 

The  'blister  copper'  is  finally  refined  to  pure  metallic  copper,  the 
most  modern  method  being  by  electroysis.  A  preliminary  refining 
treatment  is  often  given  the  'blister'  in  a  reverberatory  refining 
furnace. 

In  the  final  electrolytic  refining  operation  the  associated  gold,  silver, 
platinum  and  other  precious  and  rare  metals  are  recovered.  In  elec- 
trolytic refining  the  blister  copper  is  first  melted  and  cast  into  anodes. 
B}^  electrolysis,  cathode  copper  99.98%  pure  is  deposited.  These 
cathodes  are  melted  and  cast  into  the  various  commercial  shapes. 

The  wet  method  of  treating  or  leaching  is  used  on  carbonate  or 
oxidized  copper  ores.  The  leaching  solution  is  generally  dilute  sul- 
phuric acid  and  the  copper  is  precipitated  electrolytically  as  cathode 
copper  or  as  cement  copper,  precipitated  on  scrap  iron. 

Many  low  grade  copper  sulphide  ores  are  now  being  concentrated 
by  means  of  oil  flotation. 

CORUNDUM  AND  EMERY. 

The  demand  for  corundum  and  emery  has  increased  considerably  in 
the  last  few  years  in  the  United  States,  due  to  its  use  in  grinding 
and  polishing  metals  used  in  the  war  industries  and  due  to  decreased 
importation  from  foreign  countries.  . 

The  imports  which  come  principally  from  Turkey  and  Greece,  have 
decreased  steadily  in  the  last  several  years  owing  to  the  war's  inter- 
ference in  mining  and  shipping. 

There  has,  as  yet,  been  no  production  in  California. 

Industrial  application  and  uses. 

Most  of  the  corundum  and  emery  is  used  for  abrasive  purposes:  in 
emery  wheels,  emery  powder  or  emery  paper,  etc.,  for  polishing  and 
grinding  steel  and  glass.  In  this  regard  it  is  used  in  many  of  the  war 
industries  and  in  the  manufacture  of  munitions. 

Properties  and  ores. 

Cormidum  (Al.Og)  oxide  of  aluminum.  Color  generally  bluish 
gray;  also  blue,  green,  yellow  or  red;  vitreous  luster;  exceedingly 
hard  (hardness  9.0)  ;  specific  gravity  3.9-4.1.  Often  occurs  in  crys- 
tals quite  pure  which  are  familiarly  known  as  ruby  and  sapphire. 

Corundum  often  occurs  in  nature,  mechanically  mixed  with  a  large 
proportion  of  magnetite  and  this  material  is  the  emery  of  commerce. 
It  is  a  massive,  dark  gray  or  black  material,  nearly  opaque,  hardness 
8.0,  specific  gravity  4.0,  more  or  less  magnetic. 

Both  corundum  and  emery  are  generally  found  in  the  older  crys- 
talline rocks. 


COMMERCIAL    MINERALS    OF    CALIFORNIA.  fii 

Distribution. 

Corundum  has  been  produced  in  the  United  States  only  in  North 
Carolina  and  Georgia,  and  in  1917  the  production  came  entirely  from 
the  former  state.  There  are  undeveloped  deposits  in  other  of  the 
Appalachian  states  and  in  Montana. 

Production  of  emery  has  been  from  New  York  and  Virginia.  There 
are  deposits  in  Massachusetts,  but  there  was  no  production  from  there 
in  1917. 

No  commercial  production  has  been  made  in  California.  Good 
crystals  of  ruby  and  sapphire  have  been  found. 

Tests. 

Distinguished  by  extreme  hardness.  The  finely  pulverized  mineral 
when  made  into  a  paste  with  cobalt  nitrate  and  intensely  heated 
before  the  blowpipe  on  charcoal  assumes  a  blue  color,  due  to  aluminum. 


DOLOMITE. 

The  use  of  dolomite  as  a  refractory  in  the  steel  industry,  and  as  a 
flux  in  smelting  other  metals  has  increased  the  demand  for  this 
material. 

Industrial  application  and  uses. 

Most  of  the  dolomite  is  used  as  a  refractory  lining  in  open-hearth 
steel  furnaces,  thus  acting  as  a  substitute  for  magnesite.  It  is  also 
used  in  the  manufacture  of  carbonic  acid  gas  (CO2)  and  magnesia, 
and  as  a  flux  in  the  smelting  of  some  of  the  metals.  Recently,  the 
calcined  product  has  been  used  in  the  manufacture  of  paper  from  wood 
pulp. 

Properties  and  ores. 

Dolomite  (CaMgCOs)  calcium  magnesium  carbonate,  may  be 
regarded  as  an  intermediate  between  calcite  or  limestone  (CaCO.,) 
and  magnesite  (MgCOg).  It  is  white,  gray,  brown  or  pink  in  color, 
vitreous  to  pearly  luster,  perfect  rhombohedral  cleavage,  hardness 
3.5^.0,  specific  gravity  2.88.  Occurs  massive  or  as  rhombohedral 
crystals  wifh  curved  faces.  Much  of  the  limestone  in  California  is 
magnesian  bearing  or  dolomitic,  and  it  is  difficult  to  distinguish  be- 
tween these  minerals  and  dolomite.  It  is  commonly  associated  with 
magnesian  silicates,  especially  the  serpentine  rocks,  in  which  it  is  often 
found  as  white  veins.     It  may  be  calcined  or  burned  like  limestone. 

Distribution. 

Dolomite  is  a  very  common  mineral,  but  not  so  abundant  as  calcite. 
The  commercial  production  comes  from  quarries  in  Inyo,  San  Benito, 


38  CALIFORNIA   STATE    MINING   BUREAU. 

San  Bernardino,  Monterey  and  Tuolumne  counties.     Occurrences  have 
been  noted  in  Calaveras,  Nevada  and  Santa  Clara  counties. 

Tests. 

Fragments  effervesce  freel}^  in  hot,  but  not  in  cold  dilute  hydro- 
cWoric  acid  (HCl).  This  hydrochloric  acid  solution  when  sufficiently 
concentrated  gives  with  dilute  sulphuric  acid  (H2SO4)  a  precipitate 
of  calcium  sulphate. 

To  test  for  magnesium  disolve  a  very  small  portion  of  the  mineral 
in  a  little  hot  hydrochloric  acid,  add  a  few  drops  of  nitric  acid  to 
oxidize  the  iron  which  may  be  present,  add  water,  heat  to  boiling  and 
add  ammonia  in  excess.  Filter  off  precipitate,  if  any  has  been  found, 
add  ammonium  carbonate  or  oxalate,  filter  off  the  precipitated  calcium 
and  then  test  for  a  precipitate  of  magnesium  by  adding  sodium  phos- 
phate. 

FELDSPAR. 

California  and  the  Atlantic  seaboard  states  are  the  only  commercial 
producers  of  feldspar  in  the  United  States.  The  industry  is  a  com- 
paratively new  one  in  this  state,  the  first  production  noted  l^eiug 
in  1910. 

Industrial  application  and  uses. 

Feldspar  is  used  principally  in  tlie  manufacture  of  pottery,  china- 
ware,  porcelain,  enamel  ware,  enamel  brick,  tile,  etc.  It  is  used  in 
both  the  body  and  the  glaze  of  pottery  products,  constituting  from  10 
to  35%  in  the  body,  and  from  30  to  50%  in  the  glaze  or  enamel.  Its 
value  in  the  body  of  pottery  lies  in  the  fact  that  it  melts  during 
firing  at  a  lower  temperature  than  the  other  ingredients  and  forms 
a  firm  bond  between  the  particles  of  clay  and  quartz. 

The  newest  use  to  which  feldspar  is  now  being  put  is  its  introduc- 
tion into  the  raw  mix  in  cement  plants.  The  silica  enters  into  the 
cement  reaction,  and  the  potash  is  recovered  in  the  fine  dust  as  a  by- 
product. The  notable  increase  in  the  California  output  for  1917,  was 
due  to  this  use  by  the  cement  companies,  and  particularly  by  the 
Riverside  Portland  Cement  Company. 

Since  it  possesses  the  qualities  of  both  a  binder  and  an  abrasive 
material,  feldspar  is  quite  extensively  used  in  the  manufacture  of 
scouring  soaps  of  many  kinds,  emery,  corundum,  glass,  poultry  grit, 
roofing  material,  and  for  surfacing  concrete  work. 

Feldspar  as  a  fertilizer  is  of  value  only  under  special  conditions, 
and  attempts  to  extract  the  potash  content  are  still  in  the  experimental 
stage. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  39 

Properties  and  ores. 

The  common  feldspars  are  composed  of  silica,  alumina,  and  one  or 
more  of  the  bases — potash,  soda  and  lime. 

Orthoclase  and  microcline  (KAlSigOg)  are  potash  feldspars,  while 
albite  (NaAlSigOg)  is  the  soda  feldspar,  and  anorthite  (CaAlgSiaOg) 
is  the  lime  feldspar. 

The  great  majority  of  feldspars  are  either  mixtures  of  the  first  two 
with,  usually  an  excess  of  potash,  in  which  case  they  are  termed 
'Alkalic'  feldspar,  or  of  the  latter  two,  in  which  case  they  are 
called  plagioclase  feldspar.  All  grades  of  plagioclase  are  found  with 
compositions  varying  from  pure  albite  to  pure  anorthite.  One  of  the 
most  important  is  labradorite,  in  which  there  are  about  equal  amounts 
of  the  two  kinds. 

The  most  valuable  commercial  varieties  are  the  pure,  or  nearly  pure, 
potash  or  soda  feldspars,  because  of  the  fact  that  within  a  certain 
range  of  temperature  they  melt  without  becoming  fluid,  and  upon  cool- 
ing form  strong  and  colorless  or  light  colored  glass. 

The  feldspars  are  alike  in  general  properties.  The  cleavage  is  dis- 
tinct in  two  directions  at  right  angles  or  nearly  so,  and  not  so  per- 
fect in  a  third  direction.  The  cleavages  are  readily  seen  by  reflected 
light.  The  color  varies  from  the  pure  white,  colorless  or  porcelain- 
like appearance  of  the  plagioclase,  to  the  flesh  color,  pink  or  red,  of 
the  orthoclase.  The  luster  is  vitreous,  sometimes  pearly,  specific 
gravity  2.55-2.76,  very  hard,  scratches  glass,  hardness  6.0-7.0. 

The  requirements  for  pottery  use  are  that  the  free  quartz  should, 
for  best  results,  be  under  5%  and  in  no  case  over  20%,  the  iron-bearing 
minerals  such  as  black  mica,  hornblende,  etc.,  should  be  nearly  absent. 

Distribution. 

The  feldspar  group  is  the  most  abundant  and  most  important  of  the 
rock-forming  silicates.  The  development  of  a  deposit  upon  a  com- 
mercial basis  depends  upon  the  quantity,  quality,  distance  from  trans- 
portation, location  near  manufacturing  centers,  etc. 

During  1917  and  1918  production  was  recorded  from  Kern,  Mon- 
terey, Riverside,  San  Bernardino,  San  Diego  and  Tulare  counties. 

Tests. 

The  feldspars  are  distinguished  by  the  two  good  cleavages,  hardness, 
color  and  difficult  fusibility.  They  give  the  characteristic  yellow  flame 
tests  for  sodium,  and  less  readily,  the  pale  violet  for  potassium.  To 
test  for  potassium  and  sodium  the  powdered  mineral  is  mixed  with 
an  equal  volume  of  powdered  gypsum  and  a  little  of  this  is  inserted 


40  CALIFORNIA   STATE    MINING  BUREAU. 

on  a  clean  platinum  wire  into  the  hottest  part  of  the  Bunsen  burner 
flame.  To  observe  the  violet  color  of  potassium  a  blue  glass  is  used 
to  absorb  the  yellow  of  the  sodium. 


FLUORSPAR  AND  CRYOLITE. 

Fluorspar  is  one  of  the  non-metallic  minerals  of  moderately  small 
value,  for  which  the  demand  greatly  increased  during  the  war  because 
of  its  use  in  the  manufacture  of  steel.  Early  in  1917,  after  the  steel 
companies  liad  contracted  for  their  supply  at  $7  per  ton,  material  for 
prompt  shipment  was  scarce  and  the  price  rose  to  $21.50  per  ton.  The 
average  price  for  the  whole  year  was  $10.45  per  ton.  Early  in  1918 
prices  were  $38  to  $40  per  ton. 

Principal  production  was  reported  from  five  states:  Illinois,  Ken- 
tucky, Colorado,  New  Hampshire  and  Arizona.  The  largest  producing 
district  in  the  United  States,  if  not  in  the  world,  is  in  the  adjoining 
portions  of  southern  Illinois  and  western  Kentucky. 

No  cryolite  is  produced  in  the  United  States,  the  entire  supply  used 
in  this  country  being  imported  from  Greenland.  About  4000  tons  are 
imported  annually  and  the  average  price  in  1916  was  approximately 
$42.84  per  ton.     It  is  imported  free  of  duty. 

Industrial  application  and  uses. 

Fluorspar  is  used  as  a  flux  in  the  open  hearth  steel  furnaces,  iron 
blast  furnaces,  founderies,  and  in  gold,  silver,  copper  and  lead  smelt- 
ers; in  the  manufacture  of  glass,  pottery,  sanitary  enamel  ware,  and 
hydrofluoric  acid;  in  the  electrolytic  refining  of  lead  and  antimony, 
and  in  the  extraction  of  aluminum  from  ores.  It  is  also  used  to  some 
extent  for  glasses  in  optical  instruments,  as  a  binder  in  making  emery 
wheels,  and  carbon  electrodes,  in  the  recovery  of  potash  from  feldspar, 
and  in  Portland  cement  plants,  it  is  used  as  a  flux  to  break  up  the 
silicates. 

Cryolite  was  formerly  used  to  produce  sodium  salts  and  alum,  but 
cheaper  sources  of  these  materials  are  now  utilized.  The  more  import- 
ant uses  at  present  are  in  the  manufacture  of  opaque  white  glass,  for 
enameling  iron  ware,  in  the  manufacture  of  aluminum,  and  as  a  flux 
in  the  manufacture  of  Portland  cement. 

Properties  and  ores. 

Fluorite  (CaFg)  Fluoride  of  calcium,  commonly  called  fluorspar. 
Colorless,  white,  green,  ^.  iolet,  blue  or  yellow,  vitreous  luster,  hardness 
4.0,  specific  gravity  3,2,  perfect  octohedral  cleavage.  Usually  occurs 
in  cubes,  also  massive,  granular  or  compact.  Found  in  gneiss,  schists^ 
limestones  and  sandstones. 


COMMERCIAL   MINERALS   OP   CALIFORNIA.  41 

Cryolite  (NagAlFp,)  althougli  not  yet  produced  anywhere  in  the 
United  States,  should  be  mentioned  along  with  fluorspar  because  it  is 
the  only  other  important  fluoride  and  its  uses  are  similar  to  those  of 
fluorspar.  It  is  snow  white  to  brownish  or  reddish  in  color,  vitreous 
or  greasy  luster,  quite  soft  (hardness  2.5)  specific  gravity  2.97.  Found 
associated  with  porphyritic  granite,  the  sulphides  sphalerite,  galena, 
chalcopyrite  and  with  siderite. 

Distribution. 

Fluorspar  is  a  common  mineral,  especially  with  galena  in  lead  dis- 
tricts, sometimes  forming  thick  veins  of  commercial  value.  Deposits 
have  been  reported  in  California  from  Los  Angeles,  Mono,  San  Bernar- 
dino and  Riverside  counties,  and  in  1917  production  was  made  for 
the  first  time,  from  one  property  in  Riverside  County.  Recently,  a 
deposit  is  being  developed  near  Yermo,  San  Bernardino  County. 

Tests. 

Many  varieties  of  fluorspar  when  gently  heated  in  the  dark,  phos- 
plioresce  beautifully,  i.  e.,  become  luminous  and  give  off  purple  and 
green  light.  It  gives  the  yellowish  red  flame-test  for  calcium.  It  is 
brittle  and  when  strongly  heated  decrepitates — flies  to  pieces.  When 
finely  powdered  and  mixed  with  an  equal  volume  of  powdered  glass 
and  2  or  3  volumes  of  potassium  bi-sulphate  and  heated  in  the  closed 
tube,  the  glass  tube  is  etched  and  a  white  ring  of  silica  is  deposited. 
This  last  test  may  also  be  used  for  cryolite. 

FULLER'S  EARTH. 

In  1917  the  United  States  produced  about  82%  of  all  the  fuller's 
earth  w^hich  it  consumed.  It  is  estimated  that  the  total  domestic  pro- 
duction was  about  75,000  short  tons.  The  imports  during  the  same 
year  were  nearly  17,000  short  tons,  practically  all  of  which  came  from 
England.  The  average  yearly  production  before  1914  was  about 
35,000  short  tons. 

The  greatest  production  is  from  Forida  and  Georgia,  while  smaller 
quantities  are  produced  in  Arkansas,  California,  Colorado,  Massachu- 
setts, South  Carolina,  South  Dakota  and  Texas.  In  California,  pro- 
duction was  first  made  on  a  commercial  basis  in  1899,  and  since  then 
it  lias  been  quite  varied,  ranging  from  a  low  mark  of  50  tons  in  1908 
to  1344  tons  in  1905. 

Industrial  application  and  uses. 

The  principal  use  for  fuller's  earth  is  in  filtering,  purifying,  de- 
colorizing and  deodorizing  mineral  and  vegetable  oils,  also  animal  fats 
and  greases,  lard,  cottolene,  etc.     It  derived  its  name  from  its  early 


42  CALIFORNIA   STATE    MINING  BUREAU. 

use  by  fullers  in  removing  grease  from  cloth  or  wool.  Very  little 
is  at  present  used  for  this  purpose.  It  is  used  to  some  extent  in  the 
manufacture  of  pigments  for  printing  wall  paper,  to  detect  coloring 
matter  in  food  products,  and  as  a  substitute  for  talcum  powder. 

Properties  and  ores. 

Fuller's  earth  is  a  soft,  friable,  earthy,  clay-like  material,  gray, 
brown  or  greenish  in  color,  with  dull  or  slightly  greasy  luster.  It  is 
not  plastic  and  has  no  definite  mineral  composition,  although  in 
general  it  may  be  said  to  have  the  composition  of  the  clays,  which 
are  hydrous  aluminum  silicates,  and  generally  contain  iron,  magne- 
sium, calcium,  etc.  It  varies  considerably  in  quality  and  its  value 
depends  upon  its  texture,  i.  e.,  its  filtering  and  absorbent  properties 

Distribution. 

In  California,  the  principal  production  in  1918  came  from  Calaveras 
and  Solano  counties.  There  is  a  large  deposit  near  Elsinore  in  River- 
side County.  It  has  also  been  found  in  Monterey,  Kings  and  Fresno 
counties.  It  occurs  in  sedimentary  beds  or  may  be  derived  from  the 
weathering  of  basic  ferro-magnesian  igneous  rocks.  , 

Tests. 

There   are   no   specific   tests   for   this   material.     The   characteristic 
appearance,  physical  properties,   and  the  fact  that  it  is  non-plastic    j 
will  aid  in  its  detection,  and  as  mentioned  above,  its  valiie  must  be 
determined  by  its  quality.  ^ 


GEMS. 

The  value  of  the  gem  production  in  California  has  decreased  greatly 
in  the  last  few  years;  since  1910,  in  which  year  the  total  production 
was  valued  at  $237,475,  it  has  dropped,  often  abruptly,  until  in  1917 
it  was  $3049,  and  in  1918,  $650.  This  is  the  value  of  the  rough,  uncut 
material.  The  California  production  includes  diamonds,  beach  stones, 
chalcedony,  beryl,  tourmaline,  kunzite,  benitoite,  topaz  and  quartz 
crystals  of  rare  color.  Beryl,  tourmaline  and  quartz  were  the  most 
valuable  products  in  1917. 

The  total  value  of  the  precious  stones  produced  in  the  United  States 
in  1917  was  $131,012.  Of  this  production  corundum  with  its  varieties 
wa*s  the  largest  single  item  followed  in  order  by  quartz,  turquoise  and 
tourmaline.  These  four  made  up  about  83%  of  the  total.  Montana 
leads  the  states  in  value  of  production,  with  Nevada  second,  and 
California  third. 


"' 


COMMERCIAL    MINERALS  OP   CALIFORNIA.  43 


The  precious  stones  imported  into  the  United  States  in  1917  were 
valued  at  $34,846,351.  This  does  not  include  pearls.  The  value  of  a 
gem  stone  depends  principally  upon  its  rarity,  beauty,  purity  and 
size. 

Opinions  differ  widely  as  to  which  are  the  most  beautiful  stones. 
The  diamond  has  been  regarded  as  the  most  valuable  of  gems,  but 
some  rubies,  sapphires  and  emeralds  are  a  great  deal  more  rare  and 
often  of  greater  value.  These  four  are  regarded  by  most  everyone  as 
the  real  precious  stones.  The  popular  mind,  taste,  and  fashion  may 
change  the  standing  of  gems,  and  the  resulting  change  in  supply  and 
demand  changes  their  price  and  value. 

Industrial  application  and  uses. 

The  first  and  foremost  use  for  gems  has  always  been  for  personal 
adornment.  The  collections  of  some  of  the  ancient  rulers,  including 
the  croAvn  jewels,  were  stupendous  and  their  value  could  hardly  be 
estimated. 

In  watch-making  great  numbers  of  small  jewels  as  rubies,  sapphires, 
and  garnets  are  used,  and  in  the  cutting  of  these  many  bort  diamonds 
are  consumed.  In  diamond  drills,  black  diamonds  and  others  not 
suitable  for  gem  stones,  are  used. 

Distribution. 

Small  diamonds  have  occasionally  been  found  in  the  stream  gravels 
of  the  Sierra  Nevada  in  connection  with  gold  mining,  notably  at 
Volcano,  Amador  County,  Placerville  and  Smith's  Flat,  El  Dorado 
County;  French  Corral,  Nevada  County;  Cherokee  Flat  and  Yankee 
Hill,  Butte  County;  Gopher  Hill  and  upper  part  of  Spanish  Creek, 
Plumas  County.     The  most  productive  district  has  been  Cherokee  Flat. 

The  tourmaline  district  in  San  Diego  County  has  become  quite 
famous,  on  account  of  the  variety  and  distinctive  coloring  of  this  gem. 
The  Pala  Chief  mine  in  San  Diego  County  is  the  only  place  in  the 
world  where  the  gem  kunzite  is  found,  and  the  Dallas  mine  in  San 
Benito  County  is  the  sole  producer  of  benitoite  in  the  world.  Ruby 
and  sapphire  have  not  been  found  in  good  crystals  in  California. 
Beryl  is  found  in  the  pegmatitic  veins  with  tourmaline  in  Riverside 
and  San   Diego   counties. 

Properties. 

Any  mineral  which  is  of  value  because  of  its  particular  or  excep- 
tional beauty,  durability  or  rarity  may  be  termed  a  gem  mineral  or 
precious  stone.  Strictly  speaking,  however,  the  really  precious  stones 
are  the  diamond,  ruby,  sapphire  and  emerald  and  occasionally  the 
pearl  (animal  origin)  and  the  opal. 


44  CALIFORNIA   STATE   MINING  BUREAU. 

Diamond  is  pure  carbon    (C)    in  composition   and  is  the  hardest 
known  mineral.     It  is  brittle,  perfect  octahedral  cleavage,  colorless  to    ■ 
yellow  or  blue,  adamantine  luster,  specific  gravity  3.5. 

Euhy,  sapphire  and  Oriental  emerald  are  varieties  of  corundum 
(AI2O3)  oxide  of  aluminum.  Vitreous  luster,  hardness  9.0,  specific 
gravity  3.9-4.1.     Ruby  is  red  and  sapphire  blue,  and  emerald  green. 

Emerald  is  a  variety  of  heryl  a  silicate  of  beryllium  and  aluminum   \ 
(BegAlgSieOis)-     Color  green,  sometimes  blue,  rose  or  yellow,  vitreous 
luster,  hardness  7.5,  specific  gravity  2.63-2.8. 

Tourmaline  is  a  silicate  of  boron  and  aluminum  with  various  bases. 
Bnhellite  is  a  variety.  Colors  mostly  rose  red  and  green,  vitreous 
luster,  hardness  7.0-7.5,  specific  gravity  2.98-3.2. 

Kunzite  is  a  transparent  variety  of  spodumene,  a  lithium  aluminum 
silicate,  LiAl(  8103)2-  Beautiful  lilac  or  amethyst  color,  hardness 
6.5-7.0,  specific  gravity  3.13-3.2.     A  comparatively  new  gem  mineral. 

Benitoite  is  a  new  gem  mineral  discovered  in  1907  in  San  Benito 
County.       It    is    a    silicate    of   barium    and    titanium    (BaLiSigOg). 
Beautiful  sapphire  blue  crystals,  transparent,  vitreous  luster,  hardness    . 
6.5,  specific  gravity  3.65.  J 

Topaz  is  a  silicate  of  aluminum  and  fluorine   (AlF)2Si04. 

Chalcedony  and  Opal  are  forms  of  silica  (SiOs),  the  former  occur- 
ring in  dense  cryptocrystalline  masses,  never  transparent,  while  the 
latter  is  wholly  amorphous,  somewhat  softer  and  contains  varying 
amounts  of  water,  i.  e.,  is  hydrous.  Opal  has  a  waxy  luster,  hardness 
5.5-6.5.  Varieties  of  chalcedony  are  agate,  carnelian,  onyx,  jasper, 
flint,  sardonyx  and  bloodstone.  Varieties  of  opal  are,  wood  opal, 
moss  opal,  hydlite,  common  opal  and  precious  opal.  Most  of  the  beach 
stones  found  on  the  California  coast  and  polished  for  gems  are 
chalcedony. 

Tests. 

The  testing  of  gem  stones  must  be  left  to  those  experienced  in  that 
art.  Many  stones  may  be  recognized  by  their  color,  crystal  form, 
hardness,  structure, 'etc.,  but  their  value  in  regard  to  purity,  flawless- 
ness,  etc.,  must  be  finally  determined  under  the  microscope.  I 

GOLD. 

During  the  period  of  the  war  the  gold  producer  faced  a  peculiar 
and,  at  the  least,  a  disheartening  and  unsatisfactory  situation.  While 
practically  every  mineral  activity  in  the  state  was  stimulated  by  in- 
crease in  value  of  product,  the  gold  production  was  actually  retarded, 
because  of  no  such  increase  in  value   (since  the  value  of  gold  must 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  45 

necessarily  remain  constant)  while  there  was  a  considerable  increase 
in  practically  every  operating  cost. 

Early  in  the  war  the  government  realized  the  necessity  of  main- 
taining a  large  gold  reserve  as  a  foundation  upon  which  to  place  the 
huge  war  loans  and  maintain  the  credit  system  of  the  country.  An 
appeal  was  sent  to  the  gold  producers,  urging  them  as  their  patriotic 
duty  to  maintain  their  output. 

Great  credit  is  due  to  many  producers  who  maintained  or  even  in- 
creased their  output  under  these  unfavorable  conditions  and  without 
any  financial  aid,  often  operating  not  only  without  profit,  but  at  a 
loss.  Some  of  the  small  producers  found  it  absolutely  impossible  to 
operate  at  all. 

The  folloAving  data  is  taken  from  the  report  of  Mr.  Charles  G.  Yale, 
Statistician  in  charge  of  the  San  Francisco  office  of  the  United  States 
Geological  Survey,  Division  of  Mineral  Resources: 

Of  the  $16,539,053  production  in  California  in  1918,  $8,690,174  was 
the  output  of  deep  mines,  w^hile  $7,848,879  was  derived  from  placers. 

The  gold  dredges  produced  by  far  the  greatest  part  of  the  placer 
gold. 

Yuba  County  ranked  first  in  1918  with  a  production  of  $3,735,440, 
followed  closely  by  Amador,  $3,249,385,  and  Nevada,  $3,070,452. 
Sacramento  was  fourth,  with  a  production  valued  at  $1,694,724,  and 
Calaveras  fifth,  $865,389. 

The  three  largest  and  most  important  dredging  fields  in  the  state 
are  near  Oroville,  Butte  County;  Folsom,  Sacramento  County;  and 
]^>rarysville,  Yuba  County. 

The  largest  production  of  record  was  in  1852,  in  which  year  the 
output  was  $81,294,700. 

GRANITE. 

The  output  of  granite  in  California  has  decreased  in  the  last  few 
years  due  to  labor  shortages,  and  the  increase  in  reinforced  concrete 
and  tile  construction.  For  several  years,  1889  to  1892  inclusive,  the 
annual  production  in  California  was  valued  at  more  than  $1,000,000. 

Industrial  application  and   uses. 

Granite  is  used  most  extensiveh'  as  a  building  stone  in  modern 
construction.  It  is  extremely  durable  and  many  public  structures 
which  are  built  of  the  California  product,  present  a  beautiful  archi- 
tectural appearance.  Among  the  most  important  of  these  are  the  San 
Francisco  Civic  Center  and  the  University  of  California  Buildings, 
and  the  San  Francisco  post  office.  Granite  is  also  used  to  a  great 
extent  for  curbstones  and  monumental  work,  and  for  paving  blocks. 


46  CALIFORNIA   STATE    MINING  BUREAU. 

Distribution. 

Madera  County  is  the  largest  producer  in  the  state,  Fresno  and  . 

Placer    County   ranking   next.     The   granite   produced   at   Raymond,  | 

Madera  County,  and  Rocklin,  Placer  County,  is  of  exceptional  quality,  ; 

and  so  far  as  known  is  unexcelled.     Other  principal  producing  counties  \ 

are   Plumas,    Riverside,    San   Bernardino,    San    Diego,    Siskiyou   and  j 

Tulare.     The  Fresno  County  granite  is  dark  in  color  and  is  particu-  j 
larly  suitable  for  monumental  and  decorative  purposes. 


GRAPHITE. 

Graphite  is  a  mineral  product  of  vital  importance  in  time  of  war 
because  of  its  use  in  the  manufacture  of  crucibles  for  handling  molten 
metals.  For  this  reason  American  producers  greatly  increased  their 
output  in  1916,  1917  and  1918. 

In  1917  the  United   States  produced  about  one-fourth   of  all  the 
graphite  which  it  consumed,  taking  into  consideration  all  grades.     The 
total  domestic  production  in  this  year  was  8558  short  tons,  3301  tons  i 
of  which  was  amorphous  and  the  remainder  crj'^stalline.  | 

The  imports  which  come  mainly  from  Ceylon,  amounted  to  42,577 
tons  in  1917,  which  w^as  practically  the  same  as  the  1916  figure. 

The  extent  to  which  the  demand  for  this  material  has  increased  in 
the  last  few^  years  may  be  judged  from  the  fact  that  both  the  annual 
production  and  the  imports  for  the  last  two  years  were  approximately 
double  those  of  1914  and  1915.  The  production  in  California  has  been 
small,  due  to  the  impure  and  low^-grade  deposits  which  cannot  com- 
pete with  the  high-grade  imported  variety.  Low-grade  ores  are  con- 
centrated with  difficulty. 

The  price  for  amorphous  graphite  varies  greatly  with  the  quality, 
and  fluctations  are  also  due  to  the  varying  amounts  of  low-grade  ore 
mined.  Before  1915  the  price  ranged  from  $22  to  $30  per  ton.  In 
1916  the  average  had  dropped  to  about  $8  per  ton,  and  in  1917  it 
was  around  $12.50  per  ton. 

Industrial  application  and  uses. 

On  account  of  its  infusibility,  and  resistance  to  the  action  of  molten 
metals,  the  most  important  use  for  graphite  is  in  the  manufacture  of 
crucibles,  retorts,  and  many  other  refractories.  For  this  purpose  the 
coarse,  flake  varieties  are  alone  suited,  and  this  variety  commands 
the  highest  price.  It  is  largely  used  as  an  ingredient  of  lubricants, 
which  use  has  increased  with  the  growth  of  the  automobile  industry. 
Considerable  amounts  are  consumed  in  the  manufacture  of  lead  pencils, 
paints,  paper  and  pasteboard  products,  and  electrical  apparatus.     It 


COMMERCIAL    MINERALS   OF    CALIFORNIA.  47 

is  the  most  satisfactory  material  for  foundry  facings,  a  low-grade 
graphite  being  used.  Recently  it  has  proved  highly  efficient  in  the 
making  of  a  preparation  to  loosen  boiler  scale,  and  also  in  the  manu- 
facture of  self-lubricating  metals. 

Properties  and  ores. 

Graphite,  also  called  'black  lead'  or  plumbago,  is  pure  carbon  in 
composition.  It  occurs  in  nature  in  two  forms:  a  crystalline  or  flake 
variety,  and  an  amorphous  or  lump  graphite.  It  is  dull  black  in  color 
perfect  basal  cleavage,  occurs  in  scales  or  foliated  masses,  very  soft 
(hardness  1.0-2.0)  and  greasy.  Quite  light  (gravity  2.2).  Widely 
distributed  as  a  typical  constituent  of  metamorphic  rocks.  Often 
distributed  through  crystalline  limestone  in  minute  flakes,  and  forms 
layers  of  more  or  less  prominence  in  many  schists  and  gneisses.  In 
mining  districts  it  is  often  seen  in  the  w^alls  of  veins  mixed  with  the 
taleose  gouge.  Most  beds  of  amorphous  graphite  are  the  result  of 
alteration  of  coal  beds  by  the  intrusion  of  igneous  rocks.  This  amor- 
phous variety  is  also  made  artificially  in  the  electric  furnace. 

Distribution. 

The  amorphous  variety  comes  principally  from  Colorado,  Michigan, 
Nevada,  and  Rhode  Island;  while  crystalline  graphite  is  produced  in 
Alabama,  New  York,  Pennsylvania,  Montana,  and  to  a  small  extent, 
in  California. 

Sonoma  County  at  one  time  furnished  the  main  production  in  Cali- 
fornia, which  material  was  used  in  the  manufacture  of  paint.  Occur- 
rences have  been  reported  from  Calaveras,  Tuolumne,  Fresno,  Imperial, 
Los  Angeles,  San  Bernardino,  San  Diego,  Siskiyou,  Mendocino,  Hum- 
boldt and  Del  Norte  counties.  In  1916  t\nd  1917,  a  small  output  was 
made  by  concentration  of  a  disseminated  graphitic  schist  at  a  deposit 
in  Los  Angeles  County,  the  product  being  utilized  for  paint,  foundry 
facings  and  lubricants. 


R 


Tests. 

Distinguished  by  its  softness  and  greasy  feel.     Readily  marks  paper 
and  soils  the  fingers.     Unaffected  hy  the  blowpipe  and  acids. 


Preparation. 

Graphite  is  separated  from  the  harder  and  heavier  materials  with 
which  it  is  associated  by  crushing  and  washing.  The  lighter  spe- 
cific gravity  causes  the  graphite  to  be  floated  off  on  the  water,  while 
the  heavier  materials  are  left  behind.  Mica  cannot  be  removed  in  this 
way,  and  hence  micaceous  graphite  ores  are  of  less  value  than  others. 
The   separation    is   sometimes   made   by   simply   ])lowing   the    ground 


48  CALIFORNIA    STATE    MINING   BUREAU. 

material  by  air  currents,  the  heavier  material,  or  impurities,  falling 
first,  and  the  finer  material  being  carried  farther.  This  method  also 
serves  to  classify  the  graphite  into  different  grades  of  fineness. 


GYPSUM. 

The  gypsum  industry  was  stimulated  only  in  an  indirect  way 
by  the  war,  and  the  production  in  the  last  few  years  in  the  United 
States  has  increased  only  slightly  over  the  pre-war  figures,  but  the 
value  increased  to  a  great  extent. 

industrial  application  and  uses. 

Gypsum  is  marketed  in  both  the  raw  and  the  calcined  state.  The 
quantity  that  is  calcined  is  about  four  times  as  great  as  that  sold  as 
the  raw  material.  The  greatest  use  of  calcined  gypsum,  amounting 
to  1,500,000  tons  annually,  is  in  the  manufacture  of  plaster.  Outside 
of  the  ordinary  wall  coverings,  this  is  used  on  masonry  surfaces,  for 
decorative  mouldings,  friezes  and  panels,  in  making  plaster  board  and 
in  fire-proof  and  cold  storage  construction.  Considerable  amounts  are 
used  in  stationery  and  art  work,  beds  for  grinding  plate  glass,  foundry 
moulds,  surgical  casts,  etc. 

Raw  gypsum,  after  grinding  is  used  as  a  retarder  in  Portland 
cement,  for  land  plaster  or  fertilizer,  in  making  paints,  chalk  and 
crayons,  as  a  filler  in  cloth  and  paper  manufacture,  and  as  a  flux  in 
blast  roasting. 

Properties  and  ores. 

Gypsum  is  a  hydrous  sulphate  of  calcium  (CaS042H20).  Contains 
46.6%  SO3,  32.5%  CaO  and  20.9%  H.O.  It  is  clear  white,  light  brown, 
yellow,  or  reddish  in  color,  vitreous  or  satiny  luster,  very  soft,  may  be 
scratched  by  the  thumb  nail  (hardness  1.5)  and  light  (specific  grav- 
ity 2.3).  Occurs  in  broad  fiat  crystals,  nearly  transparent,  cleavage 
in  three  directions,  perfect  parallel  to  the  broad  face ;  or  as  the  massive 
variety  which  is  translucent  to  opaque  and  finely  granular. 

Varieties  are  selenite,  satin  spar,  alabaster  and  gypsite. 

Distribution. 

Gypsum  is  a  very  common  mineral  in  the  state,  but  extensive  de- 
posits of  a  good  pure  variety  are  exceptional.  The  mineral  occurs 
associated  with  stratified  rocks  and  is  easily  formed  by  the  action  of 
sulphate  waters  on  limestone,  consequently  small  amounts  of  the 
mineral  are  common  in  mining  regions  where  sulphides  are  decom- 
posing. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  49 

Larg-er  deposits  are  generally  formed  by  the  evaporation  of  lime 
sulphate  waters,  and  are  often  impure  due  to  mixture  with  other  salts, 
clay  and  organic  matter. 

During  1917  and  1918  there  were  producers  in  Inyo,  Riverside  and 
San  Bernardino  counties.  Occurrences  have  been  noted  in  almost 
every  mountain  or  foothill  county  of  the  state. 

The  state  of  New  York  has  for  many  years  been  the  largest  producer 
of  raw  gypsum,  followed  closely  by  Iowa,  Michigan  and  Ohio.  Largo 
quantities  are  also  produced  in  Texas,  Oklahoma,  Kansas  and 
Wyoming. 

Tests. 

The  fine  powder  in  readily  soluble  in  dilute  boiling  hydrochloric 
acid,  and  slightly  soluble  in  hot  water;  tbis  solution,  upon  the  addi- 
tion of  barium  chloride  gives  a  white  heavy  precipitate  of  barium 
sulphate.  This  distinguishes  it  from  other  sulphates  of  the  alkaline 
earths  and  some  heavy  metals.  If  the  powdered  mineral  is  fused  on 
platinum  wire  with  a  mixture  of  sodium  carbonate  and  charcoal 
powder,  and  then  transferred  to  a  moistened  silver  coin  it  will  give  a 
dark  stain  of  silver  sulphide.  If  heated  in  a  closed  tube  it  will  give 
much  Avater.  Note  extreme  softness,  scratching  by  finger  nail,  and 
excellent  eas}^  cleavage. 

Preparation. 

The  gypsum  is  prepared  for  the  market  by  first  crushing  and  then 
grinding  to  a  powder.  If  intended  for  land  plaster  it  is  put  into 
bags  or  barrels  in  this  state,  but  if  intended  for  building  plaster  it  is 
calcined.  This  is  carried  on  in  large  retorts  or  kilns,  about  eight  feet 
in  diameter  and  capable  of  holding  many  barrels  at  a  charge.  The 
powder  is  heated  until  all  the  included  water  is  given  off,  being  stirred 
continuously.  It  is  then  drawn  off  through  openings  in  the  bottom 
of  the  kettles. 

« 
INFUSORIAL  AND  DIATOMACEOUS  EARTH. 

Production  of  infusorial  and  diatomaceous  earth  in  California  has 
been  from  three  actively  operated  quarries  in  Monterey  and  Santa 
Barbara  counties.  The  first  recorded  production  was  in  1889,  when 
39  tons  were  produced. 

Tlie  average  price  varies  greatly  from  year  to  year  due  to  fluc- 
tuations in  quality  and  demand. 

Tliere  has  been  a  noticeable  increase  in  production  since  1912. 
Deposits  of  note  besides  those  in  California  are  in  Maryland,  Virginia, 
New  Jersey,  Nevada  and  Maine. 

4-2484 


50  CALIFORNIA    STATE    MINING   BUREAU. 

Industrial  application  and  uses. 

These  earths  are  used  commercially,  principally  as  absorbent  mate- 
rials, and  in  the  manufacture  of  dynamite.  They  are  also  used  in  the 
manufacture  of  polishing  powders,  scouring  soaps  and  some  refractory 
brick.  They  are  non-conductors  of  heat,  and  are  used  as  insulators. 
in  steel  plants  and  power  houses. 

Properties. 

During  Tertiary  time  certain  waters  of  the  earth  swarmed  with 
diatoms  and  infusoria,  i.  e.,  microscopic  forms  of  plant  and  animal, 
life  having  the  power  of  secreting  silica,  which  forms  their  shells  or' 
protective  coatings.  Upon  the  death  of  these  organisms,  the  siliceous 
residue  accumulates  and  forms  beds,  sometimes  up  to  50  feet  in  thick- 
ness, but  of  very  small  proportions  when  compared  with  other  forma- 
tions of  the  earth's  crust. 

In  composition  these  infusorial  and  diatomaceous  earths  are  pure 
silica,  but  most  deposits  contain  small  amounts  of  aluminum  and  iron 
oxides,  w4th  lime,  soda  and  potash.  They  are  soft,  porous  material, 
resembling  clay  or  chalk,  are  white,  gray  or  yellowish  in  col<)r.  with 
gritty  feel.  Some  idea  of  the  great  number  of  forms  which  a  deposit 
represents  may  be  gained  from  the  estimate  that  one  cubic  inch  con- 
tains 40,000,000  independent  shells. 

Distribution. 

The  most  important  deposits  of  record  in  California  are  in  ^Monterey,. 
Orange,  San  Luis  Obispo  and  Santa  Barbara  counties.  In  Santa 
Barbara  County  the  material  is  diatomaceous  and  of  good  quality.. 
Infusorial  earth  is  also  found  in  Fresno,  Kern,  Los  Angeles,  Plumas, 
San  Benito,  San  Bernardino,  San  Joaquin,  Shasta,  Sonoma  and 
Tehama  counties. 

Tests. 

This  material  can  be  distinguished  by  its  appearance  and  physical 
properties  and  its  gritty  feel.  To  test  for  silica,  £use  with  sodium 
corbonate  before  the  blowpipe,  either  on  the  platinum  wire  or  on  a 
clean  charcoal  surface.  A  glass  will  be  formed  which  is  soluble  in 
acids  and  which  upon  evaporation  will  give  a  gelatinous  precipitate 
of  silica. 

IRON. 

Iron  is  the  most  useful  of  all  the  metals  and  is  produced  in  the 
greatest  quantities.  It  has  been  known  since  earliest  history,  and  lias 
been  indispensable  to  the  development  of  civilization.  A  period  of 
extreme  activity  was  produced  by  the  war,  which  resulted  in  a  record 
output  of  iron  ore,  pig  iron  and  steel  in  1916  and  1917. 


COMMERCIAL    MINERALS   OF   CALIFORNIA.  51 

The  greatest  producing  area  is  the  Lake  Superior  district,  embracing 
Minnesota,  Michigan,  and  northern  Wisconsin.  This  region  has  pro- 
duced about  85%  of  the  total  in  the  past  several  years.  Minnesota 
J. induces  about  60%  of  the  total,  thus  furnishing  more  than  all  the 
other  states  combined.  Other  large  producing  states  are  Alabama, 
New  York,  New  Jersey,  Pennsylvania,  Tennessee,  Virginia,  Georgia, 
Colorado  and  Wyoming. 

In  California  the  production  of  iron  ore  in  1918  was  3108  tons, 
valued  at  $15,947. 

Industrial  application  and  uses. 

The  principal  products  are  pig  iron  and  various  grades  of  commer- 
cial iron  and  steel.  Considerable  quantities  are  used  in  ferro-alloys 
such  as  f  erro-manganese,  f  erro-chrome,  f  erro-silicon ;  also  as  a  fluxing 
material,  and  in  paint  manufacture. 

Properties  and  ores. 

Iron  compounds  are  very  abundant,  and  furnish  most  of  the  common 
coloring  material  in  soils  and  rocks.  Pure  or  native  iron  is  found 
in  meteorites,  and  in  small  grains  in  some  igneous  rocks.  Of  the 
many  iron  ores  the  oxides  are  the  most  important  in  the  iron  and 
steel  industry.  Hematite  has  always  been  the  principal  ore  and 
in  the  last  few  years  has  constituted  in  the  neighborhood  of  94% 
of  the  iron  ore  mined.  Other  ores  are  limonite  and  magnetite. 
The  carbonate  is  insignificant  in  comparison  with  the  other  ores.  The 
sulphides  are  abundant,  but  are  not  of  commercial  importance  as 
regards  the  iron  content. 

Native  Iron  (Fe)  is  usually  massive,  iron-gray  color  and  streak, 
metallic  luster,  malleable,  ductile,  magnetic,  hardness  4.5,  specific 
gravity  7.5. 

Hematite  (Fe203).  Red,  brown,  steel-gray  or  black  in  color,  red- 
dish brown  streak,  metallic,  submetallic  or  earthy  luster,  hardness 
5.5-6.5,  specific  gravity  4.9-5.3.  Occurs  massive,  with  prominent 
reniform  or  kidney-shaped  structure  and  often  earthy,  granular, 
crystalline  or  micaceous.  Contains  70%  iron  and  30%  oxygen.  The 
black  crystalline  masses  are  found  with  the  crystalline  metamorphic 
.or  igneous  rocks,  while  the  red  earthy  masses  are  sedimentary  altera- 
tions of  iron-bearing  minerals.  The  flaky  'specular  hematite,'  is 
common  in  crystalline  rocks. 

Limonite  (2Fe203).  Color  yellow,  brown  or  black,  streak  yellowish 
brown,  submetallic  to  dull  luster,  hardness  5.0-5.5,  specific  gravity 
3.6-4.0.     Occurs    massive,    earthy,    fibrous,    columnar,    botryoidal    or 


52  CALIFORNIA   STATE   MINING  BUREAU.  j 

stalactitic.  One  of  the  most  common  of  the  iron  minerals.  Common 
alteration  product  of  pyrite  and  other  iron  minerals,  and  with  hematite 
forms  the  great  gossan  cappiugs  of  iron  sulphide  deposits. 

Magnetite  (Fe304).  Magnetic  iron.  Color  iron  black,  streak  black, 
metallic  luster,  hardness  5.5-6.5,  specific  gravity  5.1.  Strongly  mag- 
netic. Occurs  massive,  granular  or  as  octahedral  crystals.  One  of , the 
most  abundant  iron  minerals  and  ranks  next  to  hematite  as  an  ore. 
Occurs  in  igneous  rocks,  or  metamorphic  gneisses  and  schists,  often 
along  the  contacts  of  igneous  intrusions. 

Distribution. 

There  are  many  deposits  of  iron  ore  in  California,  some  of  which 
are  of  considerable  size,  but  production  has  been  limited  on  account 
of  the  lack  of  a  suitable  supply  of  coking  coal.  Up  to  the  present, 
the  production  has  been  utilized  principally  in  the  manufacture  of 
the  ferro-alloys  by  means  of  the  electric  furnace.  The  Minaret  iron, 
deposit  in  Madera  County,  said  to  be  the  largest  in  the  state,  is  com- 
posed of  magnetite  and  has  been  estimated  to  contain  at  least  30,000,000 
tons  of  iron  ore.  There  are  several  extensive  deposits  in  Shast;i 
County.  Other  deposits  of  note  are  in  San  Bernardino,  Riverside 
and  Placer  counties.  The  1918  production  was  from  San  Bernardino 
and  Shasta  counties. 

In  addition  to  the  electric  smelters  of  the  Noble  Electric  Steel  Com^ 
pany  at  Heroult,  Shasta  County,  and  the  Pacific  Electro  Metals  Com-) 
pany  at  Bay  Point,  Contra  Costa  County^  both  of  which  manufacture 
ferro-alloys,  there  are  two  blast  furnaces  now  said  to  be  in  operation,^ 
one  in  Shasta  and  one  in  San  Bernardino  County. 

Tests. 

Iron  compounds  are  strongly  magnetic  after  heating,  before  thd 
blowpipe  in  the  reducing  flame.  Magnetite  is  strongly  magnetic  before 
heating,  and  hematite  is  often  slightly  so.  Limonite  and  hematite 
are  often  easily  distinguished  by  their  color,  streak  and  characteristi 
structures. 


Metallurgy. 

Iron  is  extracted  most  easily  from  the  oxide  ores.  These  are  crushed 
and  roasted,  and  then  smelted  in  blast  furnaces  with  coke  or  coal,  and 
a  flux  of  limestone,  feldspar,  etc.  The  carbon  reduces  the  oxide  to 
metallic  iron,  which  collects  in  molten  form  at  the  bottom  of  the  fur- 
nace, while  the  flux  removes  the  impurities  from  the  ore  and  forms  a 
'slag.' 


COMMERCIAL   MINERALS  OP   CALIFORNIA.  53 

The  ore  is  dumped  into  the  furnace  at  the  top  with  50%  to  65% 
of  its  weight  of  coke,  together  with  limestone,  feldspar  or  other  flux 
necessary  to  form  a  pre-determined  slag.  Combustion  is  maintained 
by  the  introduction  of  hot  air  at  500°  to  750°  Centigrade,  through 
openings  at  the  bottom  called  'tuyeres.'  The  furnaces  are  often  100 
feet  high,  and  are  kept  constantly  filled  with  charge.  The  slag  and 
iron  are  tapped  off  at  regular  intervals,  the  iron  being  run  into  moulds 
<nid  called  'pig  iron.'  The  'pig  iron'  generally  contains  from  3% 
lo  4%  carbon,  0.5%  to  3%  silica  and  small  amounts  of  sulphur  and 
{)hosphorus.  It  is  later  refined  and  converted  into  the  various  grades 
(if  iron  and  steel. 

LEAD. 

Missouri  is  the  largest  lead  producer  among  the  states,  followed  by 
Utah,  Colorado,  Oklahoma,  Arizona,  California  and  ^Montana. 

Industrial  application  and   uses. 

Lead  is  used  extensively  for  war  munitions — bullets,  shells,  car- 
tridges, shrapnel,  bombs,  etc.  For  these  purposes  it  is  generally 
alloyed  with  a  little  arsenic  or  antimony.  It  is  used  to  a  great  extent 
for  pipes  of  various  sizes  and  shapes  because  of  its  resistance  to 
corrosion,  and  because  it  can  be  easily  bent  and  cut  and  can  be  made 
into  any  length  desired  by  soldering.  Lead  pipe  is  extensively  used 
for  carrying  copper  Avires  both  overhead  and  underground.  Many 
alloys  as  solder,  type  metal,  pewter,  brass  and  bronze,  contain  varying 
amounts  of  this  metal.  It  is  made  into  sheets  and  used  for  roofs,  to 
line  sinks,  cells  in  electrolytic  processes  and  in  metallurgical  apparatus. 
So-called  red  lead  (an  oxide,  PbgO^)  and  wliite  lead  (basic  lead 
carbonate)  are  extensively  used  in  paint  manufacture.  Litharge 
(PbO)  is  used  as  a  flux  in  assaying. 

Properties  and  ores. 

Native  or  metallic  lead  (Pb)  is  a  soft,  heavy  lead-gray  metal,  bright 
metallic  luster  when  freshly  cut,  but  usually  tarnished  to  dull  or  sub- 
metallic.  It  is  very  malleable  and  melts  easily.  Hardness  1.5,  specific 
gravity  11.37.  Seldom  found  in  nature  in  this  form.  Galena,  with 
its  alteration  products,  cervissite  and  anglesite,  are  the  principal  ores. 

Galena  or  galenite  (PbS).  Lead  sulphide.  Color  lead-gray,  streak 
dark  gray,  metallic  luster,  perfect  cubic  cleavage,  hardness  2.5,  specific 
gravity  7.3-7.6.  Contains  86.6%  lead  and  13.4%  sulphur.  Occurs 
in  cubes,  also  massive,  lamellar  or  foliated.  Common  in  gold,  silver 
and  copper  districts. 


54  CALIFORNIA   STATE   MINING  BUREAU. 

Cerussite  (PbCOg)  lead  carbonate.  Color  gray,  cream  or  brown, 
vitreous  to  adamantine  luster,  hardness  3.0-3.5,  specific  gravity 
6.46-6.57.  Generally  occurs  massive,  and  is  a  common  alteration 
product  of  galena,  and  is  often  a  rich  silver  ore.    . 

Anglesite  (PbSO^)  lead  sulphate.  Colorless,  wlciite  yellow,  gray  or 
brown,  adamantine  luster,  hardness  2.5-3.0,  specific  gravity  6.35. 
Occurs  massive  or  in  prismatic  crystals.  Common  oxidization  product 
of  galena,  but  usually  found  in  small  amounts. 

Wulfenite  (PbMoO^)  molybdate  of  lead.  Color  orange-yellow  to 
bright  red,  adamantine  luster,  hardness  3.0-4.5,  specific  gravity 
6.0-7.0.  Occurs  massive  or  in  thin  tabular  crystals.  Also  described 
under  molybdenum. 

Distribution. 

Lead  produced  in  California  comes  principally  from  Inyo  County, 
which  produced  91%  of  the  total  in  1918.  Other  principal  producing 
counties  in  order  are  San  Bernardino,  Kern  and  Shasta.  It  is  usually 
found  in  gold,  silver  and  copper  districts,  and  is  commonly  associated 
with  the  sulphides  of  zinc,  copper,  iron  and  with  barite,  fluorite  and 
calcite. 

Tests. 

Lead  compounds  when  fused  on  charcoal  with  sodium  carbonate, 
before  the  reducing  flame  of  the  blowpipe,  give  metallic  globules  of 
lead  and  a  coating  of  oxide  which  is  sulphur  yellow  near  the  assay 
and  bluish  white  a  short  distance  away.  Galena,  when  roasted  in  the 
open  tube  gives  off  sulphur  dioxide;  it  is  oxidized  by  concentrated 
nitric  acid,  with  usually  the  separation  of  lead  sulphate  and  also  some 
sulphur.  Cerussite  is  soluble  in  warm  dilute  nitric  acid  Avith  effer- 
vescence (evolution  of  carbon  dioxide  gas).  In  the  closed  tube,  when 
heated  it  decrepitates  (breaks  up)  and  is  changed  to  lead  oxide  which 
is  dark  yellow  when  hot. 

Metallurgy. 

Lead  is  derived  from  its  ores  by  methods  of  roasting  and  reduction 
in  both  blast  and  reverberatory  furnaces. 

Galena  containing  gold,  silver  and  other  valuable  metals,  also  the 
oxidized  ores,  (oxides  and  carborates)  are  treated  in  blast  furnace. 
The  charge  consists  of  coke,  ore  and  fluxes.  The  lead  is  separated 
from  the  ore  and  collected  as  'base  bullion.'  The  sulphur  forms 
with  the  copper  and  iron  a  'matte,'  while  the  remaining  bases  unite 
with  the  silica  to  form  'slag.'  If  there  are  not  basses  enough  in  the 
original  ore  to  form  a  suitable  slag,  fluxes  must  be  added. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  55 

The  'base  bullion'  is  refined  for  the  production  of  pure  lead,  and 
the  recovery  of  the  gold,  silver  and  other  precious  metals.  The  lead 
copper  'matte'-  is  resmelted  and  refined.  High  grade  non-siliceous 
ores  containing  little  silver,  are  best  treated  by  roasting  and  reduction 
in  the  reverberatory  furnace.  This  process  may  be  divided  into  two 
stages,  namely  oxidation  and  reduction.  The  ore  is  ground  fine,  spread 
out  evenly  over  the  hearth,  and  heated  for  several  hours,  at  compara- 
tively loAv  temperature  (500°  to  600°  Centigrade).  The  charge  is 
frequently  raked  over  to  expose  new  surface  to  the  action  of  the  heat 
and  air.  Only  part  of  the  galena  is  changed  to  lead  sulphate,  the 
remainder  being  unaltered.  The  temperature  is  then  raised  to  about 
700°  Centigrade,  when  the  oxide  and  sulphate  formed  in  the  first 
stage,  re-act  with  the  unchanged  galena,  producing  metallic  lead,  which 
flows  down  the  inclined  hearth  and  collects  in  a  basin,  while  the 
sulphur  dioxide  gas  passes  off  through  the  flue.  Slaked  lime  is  often 
added  to  stiffen  the  charge  and  to  make  it  spongy. 

The  process  of  oxidation  and  reduction  is  repeated  several  times, 
before  the  greater  part  of  the  lead  is  obtained  from  the  charge,  eacli 
successive  operation  being  shorter  and  the  temperature  higher.  To- 
wards the  end,  coal  or  charcoal  is  added  for  further  reduction.  The 
slag  residue  may  still  contain  considerable  lead,  and  this  is  treated 
in  the  blast  furnace.  The  refining  of  the  bullion  is  accomplished  by 
electrolysis. 

MAGNESITE. 

The  demand  for  magnesite  greatly  increased  during  the  war,  because 
of  its  extensive  use  for  refactory  linings  in  all  kinds  of  smelting 
furnaces,  and  because  of  its  numerous  other  applications  which  made 
it  indirectly  of  great  value  as  a  war  mineral.  As  a  refractory  it 
is  a  substitute  for  chromite.  It  thus  released  much  of  the  latter 
mineral  for  use  in  the  manufacture  of  steel. 

For  several  years  previous  to  the  war  the  United  States  produced 
only  approximately  6  or  7%  of  the  total  amount  of  the  magnesite 
consumed,  the  imports  coming  chiefly  from  Austria  and  Greece.  The 
home  production  was  forced  to  supply  not  only  the  tonnage  of  imports 
Avhich  were  almost  entirely  cut  off,  but  also  the  increased  demand  at 
home.  The  country  turned  to  California  for  this  supply  because  for 
many  years  previous  to  1916  this  state  was  the  sole  producer  of  mag- 
nesite. The  results  are  shown  by  the  fact  that  in  1917  the  production 
was  fKV;  of  the  consumption.  In  that  year  the  State  of  Washington 
showed  considerable  output. 


56  CALIFORNIA   STATE    MINING  BUREAU. 

Industrial  application  and  uses. 

The  principal  uses  are :  refractory  linings  for  steel  furnaces,  copper 
reverberatories  and  converters,  bullion  and  other  metallurg'ical  fur- 
naces, sanitary  flooring  in  office  buildings,  hospitals,  ship  decks,  rail- 
road cars,  kitchens,  etc.  It  is  also  used  in  the  manufacture  of  paint, 
paper  and  medicines. 

The  best  refractory  material  is  made  by  'dead  burning'  the  mag- 
nesite,  i.e.,  driving  off  practically  all  of  the  carbon  dioxide  (CO.) 
leaving  magnesia  (MgO).  For  cement  purposes  it  is  left  caustic,  that 
is,  5%  to  107o  of  the  COg  is  retained. 

Magnesium  powder  is  used  in  fireworks  and  in  flash  light  powder. 

Properties  and  ores. 

Magnesium,  although  never  found  free  in  nature,  is  the  basis  for 
many  common  minerals.  It  is  a  silvery  white  metal,  metallic  luster, 
very  light  (specific  gravity  1.75),  tenacious  and  ductile.  When  hot 
it  can  be  drawn  into  wire  or  ribbon,  the  latter  being  a  common  com- 
mercial form.  It  melts  easily  and  burns  with  a  dazzling  white  light, 
producing  dense  white  clouds  of  magnesium  oxide. 

Magnesite  (MgCOg)  magnesium  carbonate,  is  the  common  ore  of 
magnesium.  Contains  47.6%  MgO  and  52.4%  COg.  It  is  snow  white 
to  brown  in  color.  Vitreous  to  silky  luster.  Hardness  3.5-4.5.  Grav- 
ity 3.0-3.2.  Quite  brittle.  Generally  compact,  massive  with  conchoi- 
dal  fracture.  Usually  associated  with  magnesian  rocks,  especially  ser- 
pentine, from  which  it  is  an  alteration  product.  Sometimes  associated 
with  limestone  and  gypsum. 

Occurrence. 

Magnesite  is  a  very  common  mineral  in  California  because  of  the 
great  areas  of  serpentine  in  the  Coast  Range  and  the  Sierra  Nevada. 
Much  of  it  is  very  high  grade,  some  deposits  yielding  above  95% 
MgCOo.  The  Porterville  district  in  Tulare  County  is  one  of  the 
most  important  in  the  state.  In  Sonoma,  Santa  Clara  and  Napa 
counties  are  several  large  deposits.  Considerable  tonnage  has  also 
been  produced  in  Kern,  Riverside,  Fresno   and  Mendocino  counties. 

Tests. 

Magnesite  is  not  acted  upon  by  cold  dilute  hydrochloric  acid  (HCl), 
but  dissolves  readily  with  effervescence  in  hot  acid.  If  the  solution 
is  made  strongly  alkaline  with  ammonia,  and  sodium  phosphate  added, 
a  white  crystalline  precipitate  will  be  formed.  Before  testing,  how- 
ever, it  must  be  ascertained  wliether  other  substances  are  present  which 
would  tend  to  form  a  precipitate.     A  good  procedure  is  as  follows: 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  57 

Dissolve  a  very  small  portion  of  the  mineral  in  a  small  quantity 
of  boilins:  hydrochloric  acid,  add  a  drop  or  two  of  nitric  acid  and 
then  water,  and  again  heat  to  boiling.  Add  ammonia  in  excess,  and 
filter  if  there  is  a  precipitate.  To  the  filtrate  add  ammonium  carbonate 
or  oxalate  and  again  filter.  Then  add  sodium  phosphate  for  the 
precipitate  described  above. 

Preparation. 

The  ore  is  sometimes  shipped  raw,  in  which  case  it  goes  to  the 
steel  mills,  but  more  often  it  is  calcined  at  the  mines,  in  rotary  or 
vertical  shaft  kilns,  and  the  calcined  product  sold  to  the  plastic  trade. 
The  rotary  kiln  is  the  most  modern  and  is  coming  into  general  use. 

MANGANESE. 

In  1917  the  production  of  manganese  in  the  United  States  was 
approximately  one-third  of  tte  amount  consumed.  The  recent  in- 
crease in  the  consumption  of  this  material  in  the  manufacture  of 
steel  has  been  supplied  almost  entirely  by  augmented  home  produc- 
tion, as  the  imports  for  1917  were  but  little  more  than  during  the 
previous  year.  The  imports  come  mainly  from  Brazil.  California 
has  played  an  important  part  in  this  regard,  as  may  be  seen  from  the 
following  figures:  The  production  for  1915  was  4013  tons,  valued 
at  $49,098 ;  for  1916  it  was  13,404  tons,  valued  at  $274,601 ;  for  1917 
it  was  15,515,  valued  at  $396,659;  and  for  1918  it  was  26,075  tons, 
valued  at  $979,235.  In  1917  the  total  approximate  production  of 
the  United  States  was  113,734  tons. 

The  silica  content  should  not  be  over  8%,  although  higher  percent- 
ages are  allowed  with  penalty. 

Industrial  application  and   uses. 

Most  of  the  manganese  consumed  in  the  United  States  goes  into  the 
manufacture  of  ferro-manganese,  which  is  used  in  removing  certain 
impurities  from  steel ;  it  is  also  used  in  the  manufacture  of  very  hard, 
high  grade  steel,  which  is  in  great  demand  at  the  present  time.  It 
is  used  to  a  smaller  extent  in  the  manufacture  of  glass,  electric  dry 
batteries,  paint,  pottery,  tile  and  brick. 

Properties  and  ores. 

The  metal  manganese  (Mn)  is  not  found  free  in  nature,  but  we 
recognize  it  through  its  compounds  or  ores.  Three  of  these  are  of 
distinct  commercial  value,  the  most  important  of  which  are  the  oxides, 
i.  e.,  manganese  in  combination  with  oxygen.  The  first,  manganese 
dioxide  (MnO2.MnoO3.II2O),  called  Psilomelane,  is  the  most  important. 


58  CALIFORNIA   STATE    MINING   BUREAU. 

It  is  iron  black  or  greenish  black  in  color,  and  gives  a  dull  black  streak. 
It  is  very  heavy  (specific  gravity  -4.4)  and  quite  hard  (hardness 
-5.0-6.0).  When  broken  it  presents  a  shelly  appearance,  resembling 
that  of  broken  glass,  and  has  a  sub-metallic  luster.  Its  characteristic 
occurrence  is  in  irregular  masses  with  smooth  surfaces  in  jasper  in 
the  Coast  Ranges  and  in  slates,  shales  and  igneous  rocks  of  the  Sierra 
Nevada.  The  other  important  oxide,  Pyrolusite  (MnOs)  is  iron 
black  in  color,  v/ith  a  black  streak;  63.2%  Mn.  36.8%  0.  It  is  much 
softer  than  the  ore  mentioned  above  (hardness  2.0-2.5)  and  slightly 
heavier  (specific  gravity  -4.8).  It  has  a  sub-metallic  luster  and  when 
broken  appears  splintery.  Generally  occurs  massive,  although  some- 
times in  coatings  or  as  a  powder. 

Other  less  important  oxides  are  Manganite  and  Braunite,  both  of 
which  are  heavy  black  minerals,  with  black  or  brownish  streak,  aii<[ 
more  or  less  metallic  luster.  Manganite  generally  occurs  in  lar^c 
porous  masses  with  columnar  structure  in  jasper  or  altered  rocks. 
Braunite  occurs  in  either  massive  or  crystalline  form. 

Besides  the  oxides  mentioned  above,  and  quite  in  contrast  to  them, 
is  the  carbonate,  Rhodochrosite  (MnC03).  This  mineral  is  rose  red 
in  color,  with  pearly  or  vitreous  (glassy)  luster.  Often  found  in 
gold  and  silver  regions  associated  with  the  veins.  May  occur  in  masses 
or  in  small  crystals. 

Distribution. 

The  majority  of  the  manganese  deposits  of  which  the  Mining  Bureau  : 
has  record,   are  located  in  the   Coast  Range.     They  are  widely  dis- 
tributed from  Siskiyou  County,  southerly  through  Trinity,  Humboldt, 
Tehama,  Mendocino,  Glenn,  Lake,  Sonoma  and  Napa  counties. 

Further  south  there  is  a  prominent  belt  including  the  easterly 
portions  of  Alameda,  Santa  Clara  and  San  Benito  counties  and  the 
westerly  portion  of  San  Joaquin,  Stanislaus  and  Merced  counties. 
There  are  several  deposits  in  the  northwestern  part  of  San  Luis  Obispo 
County.  In  the  foothills  of  the  Sierra  Nevada  are  several  deposits,  \ 
principally  in  Plumas,  Butte,  Nevada,  Amador  and  Tuolumne  coun- 
ties. A  few  properties  are  located  in  San  Bernardino,  Riverside  and 
Kern  counties. 

Tests. 

Easy  field  tests  for  manganese  ores  may  be  made  as  follows : 
Make  a  borax  bead  by  dipping  a  loop  of  fine  platinum  wire  into  ^ 
l)o\vdered  borax,  and  heating  until  reduced  to  a  clear  glass.     A  very 
.small  piece  or  a  little  of  the  powder  of  the  mineral  will  color  this 
bead  a  deep  amethyst  when  hot  and  reddish  brown  when  cold.     When 
fused  with  soda,  manganese  ores  give  an  opaque  green  bead.     This 


COMMERCIAL    MINERALS  OF   CALIFORNIA.  59 

lest  gives  best  results  if  a  little  potassium  nitrate  (KNO3)  is  added 
Tor  thorough  oxidization.  Pyrolusite,  when  heated  in  the  closed  tube, 
liives  off  oxygen  gas.  Its  softness  is  also  one  means  of  distinguishing 
it.  Ehodochrosite,  when  treated  with  dilute  hydrochloric  acid,  effer- 
vesces and  gives  off  carbon  dioxide  gas  (COo). 

Metallurgy. 

Ores  containing  more  than  40%  manganese  and  generally  less  than 
15%  silica  are  smelted  to  ferro-manganese  w^hich  contains  70-80% 
manganese,  12-20%  iron  and  6-7%  carbon. 

Lower  grade  ores  are  smelted  to  '  spiegeleisen, '  a  ferro-mangane.se 
which,  in  most  cases,  contains  from  15  to  20%  manganese,  70-75% 
iron  and  -1-5%  carbon. 

Manganiferous  zinc  residuum  is  also  smelted  to  spiegeleiseu. 

In  the  open  hearth  process  of  making  manganese  steel,  the  ferro- 
manganese  is  used,  while  in  the  Bessemer  process,  spiegeleiseu  is  used. 

For  use  in  the  manufacture  of  dry  batteries  very  high  grade  ore 
is  required. 

MARBLE. 

There  are  many  beautiful  marbles  in  this  state,  which  are  of  durable 
quality,  but  the  production  has  decreased  in  recent  j^ears  due  to  the 
fact  that  the  foreign  marbles  and  that  from  eastern  states  and  Alaska 
can  often  be  shipped  here  by  water  cheaper  than  the  local  product 
can  be  marketed. 

The  principal  producing  states  are  Vermont,  Pennsylvania,  Mass- 
achusetts, Maryland,  Georgia  and  Kentucky.  No  recent  data  for 
the  total  domestic  production  is  available,  but  in  1915  the  production 
in  the  United  States  was  valued  at  almost  $7,000,000. 

The  Italian  marble  is  the  most  famous  in  the  world,  and  is  pro- 
duced in  the  greatest  quantities.  Other  principal  producers  are 
France.  Greece,  Spain  and  Mexico. 

Industrial  application  and   uses. 

Marble  is  used  extensively  as  a  building  material,  principally  in 
interior  finishings  of  a  highly  decorative  nature,  such  as  courts  and 
corridors  in  public  and  office  buildings,  hotels,  apartment  liouses  and 
private  residences.  The  great  varieties  in  color  and  the  high  polish 
which  it  takes,  make  it  possible  to  produce  beautiful  decorative  effects. 
Great  quantities  are  used  for  statuary,  monuments,  etc. 

Properties. 

Marble  may  be  pure  calcite  (CaCOJ,  may  be  magnesian  or  dolomitic, 
or  may  be  pure  dolomite   (CaMgCOg).     Much  of  the  marble  in  this 


60  CALIFORNIA   STATE   MINING  BUREAU. 

state  is  dolomitic.  It  has  a  highly  crystalline  or  granular  texture  and 
may  be  almost  any  color  from  pure  white  to  reddish,  due  to  natural 
coloring  materials  such  as  iron,  manganese,  etc.  Hardnes.s,  3.0,  spec- 
ific gravity  2.25-2.75.  Easily  cut  into  various  shapes  or  slabs  of  large 
size  and  takes  a  high,  beautiful  polish. 

Distribution. 

The  marble  produced  in  California  comes  from  quarries  in  Inyo 
and  Tuolumne  counties.  It  also  occurs  in  Amador,  Butte,  Kern,  San 
Bernardino,  Santa  Cruz,  Siskiyou,  Solano  and  Tulare  counties. 

Tests. 

All  marbles  effervesce  freely  i.  e.,  give  off  carbon  dioxide  gas,  when 
treated  with  dilute  h^^drochloric  acid.  The  acid  may  have  to  be 
warmed  slightly  before  action  will  start.  Most  marbles  are  also  easily 
distinguished  by  color  softness  and  general  appearance. 


MICA  AND  LITHIA. 

Mica  became  of  some  importance  as  a  war  mineral  through  its  use  as 
windows  in  gas  masks,  armored  cars,  protective  goggles,  and  similar 
uses  where  it  was  substituted  for  glass,  and  as  an  insulating  material 
in  electrical  apparatus. 

There  has  been  no  marked  effect  upon  the  production  during  the 
war,  but  the  price  increased  considerably.  The  total  value  of  mica 
produced  in  the  United  States  in  1917  was  $757,346,  about  93%  of 
this  value  being  in  sheet  mica.  This  was  the  highest  value  of  record, 
althougli  the  quantity  produced  w^as  smaller  than  for  several  years. 

North  Carolina  was  the  largest  producer,  with  New  Hampshire 
second.  Small  amounts  were  produced  in  Virginia,  South  Dakota, 
Georgia  and  Alabama.  The  domestic  production  for  the  past  several 
years  has  averaged  in  the  neighborhood  of  38%  of  the  total  consump- 
tion. In  1917  the  imports  were  valued  at  $1,429,004  and  came  mainly 
from  Canada,  England,  India,  Argentine  and  Brazil.  There  was  a 
small  production  in  California  in  1902,  1903  and  1904,  but  there  has 
been  none  reported  since  then. 

Lithia  was  produced  in  San  Diego  County  for  several  years  from 
1899  to  1905,  but  there  was  no  production  from  the  latter  date  until 
1915,  when  91  tons  were  mined,  valued  at  $1365.  In  1918  there  were 
4111  tons  produced  valued  at  $73,998.  The  latter  was  lepidolite  from 
San  Diego  County. 


COMMERCIAL    MINERALS   OF   CALIFORNIA.  61 

Industrial  application  and  uses. 

The  industrial  value  of  mica  lies  in  Its  great  resistance  to  heat  and 
acids,  its  perfect,  easy  cleavage,  its  transparency  and  its  insulating 
properties.  Sheet  mica  finds  its  greatest  use  in  the  electrical  industry 
in  the  construction  of  dynamos,  electric  light  sockets,  spark  plugs, 
insulators,  fuse  boxes  and  telephones.  It  is  also  used  in  place  of 
glass  for  windows,  lamp  chimneys,  automobile  curtain  windows,  stove 
fronts,  portholes,  peepholes  in  furnaces,  etc.  Ground  mica  is  used  in 
fancy  paints  and  wall  paper,  to  which  it  gives  luster  and  brightness; 
in  the  manufacture  of  ornamental  tile,  insulating  and  fire-proofing 
compounds  and  paints,  pipe  and  boiler  coverings,  patent  roofing  mate- 
rial, gunpowder,  blasting  powder,  etc.,  as  a  lubricant  when  mixed 
with  oil,  in  making  rubber  goods,  and  in  calico  printing. 

Lithia  is  used  in  the  preparation  of  lithia  salts,  the  metal  lithium, 
mineral   water,    fireworks,    and   signal   rockets. 

Properties  and  ores. 

The  micas  embrace  a  number  of  silicates  of  potassium,  aluminum, 
sodium,  and  magnesium.  Their  characteristic  occurrence  is  in  thin 
elastic  scales  and  plates.  Of  the  many  varieties  the  most  important 
from  a  commercial  standpoint  is  muscovite,  but  phlogopite  and  biotite 
are  sometimes  of  value. 

Muscovite  (HKAlSiO^).  Hydrous  silicate  of  potassium  and 
aluminum.  Colorless,  gray,  brown,  or  pale  green,  vitreous  or  pearly 
luster,  perfect  basal  cleavage,  soft  (hardness  2.0-2.5,  and  light  (spe- 
cific gravity  2.7-3.0).  Occurs  in  scales,  hexagonal  plates  or  sheets. 
Very  common  in  granite,  syenites,  schists  and  gneisses. 

Phlogopite.  Properties  similar  to  above  except  in  color,  which  is 
pearl  gray,  yellowish  brown  or  green. 

Biotite.  Properties  same  as  above,  except  that  color  is  dark  green 
or  black  and  luster  is  more  resplendent. 

Lepidolite.  Lithia  mica.  Silicate  of  lithium,  potassium,  aluminum 
and  fluorine.  Color  lilac,  lavender,  violet  or  pink,  commonly  in  scaly 
masses  with  pearly  luster,  associated  with  tourmaline.  Perfect  basal 
cleavage,  hardness  2.5-4.0,  specific  gravity  2.8-2.9.  Less  common  than 
the  other  micas. 

Distribution. 

Although  mica  occurs  in  almost  all  granitic  and  gneissoid  rocks,  it 
is  not  commonly  of  sufficient  size  to  be  of  commercial  value.  It  is  :i: 
pegmatite  and  coarsely  f eldspathic  veins,  and  in  the  case  of  phlogopite, 
in  calcareous  rocks  associated  with  eruptive  pyroxenites,  that  it  is  of 
valuable  size. 


62  CALIFORNIA   STATE   MINING  BUREAU. 

Tests. 

The  micas  are  easily  distinguished  by  their  perfect  cleavage,  pearly 
luster  and  color.  Lepidolite  has  distinguishing  colors  and  responds 
to  the  test  for  lithia,  i.  e.,  gives  a  lilic-red  color  when  moistened  with 
hydrochloric  acid  and  held  on  a  platinum  wire  in  the  flame.  It  is 
easily  fusible  to  a  white  or  gray  globule,  and  gives  acid  Avater  when 
intensely  ignited  in  the  closed  tube.  Muscovite  is  scarcely  acted  upon 
by  boiling  concentrated  sulphuric  acid,  while  biotite  and  phlogopite, 
when  similarly  treated  are  decomposed,  and  the  acid  becomes  turbid. 

Preparation. 

There  is  a  great  waste  in  preparing  the  sheet  mica  for  the  market. 
The  first  step  in  the  process  is  to  cut  the  sheets  to  certain  patterns, 
which  most  closely  fit  the  sizes  of  the  natural  plates.  They  are  cut 
with  large  shears,  one  leg  of  which  is  firmly  fastened  on  a  large  table. 
Then  the  plates  are  'cleaned'  by  holding  them  up  to  the  light  of 
a  window,  and  the  outside  pieces,  if  they  contain  flaws,  are  stripped 
off.  This  process  is  continued  until  a  clear  flawless  sheet  remains. 
One  hundred  pounds  of  black  mica,  yields  on  an  average  15  or  20 
pounds  of  the  finished  product.  The  waste  mica  is  ground  and  used 
for  the  various  purposes  mentioned  above. 

MINERAL  PAINT. 

The  iron  oxides,  hematite  and  limonite,  are  the  most  valuable  of  the 
state's  mineral  pigments.  The  jasper  produced  is  of  value  on  account 
of  the  color,  which  is  probably  due  to  oxides  of  iron  and  manganese. 

Industrial  application  and  uses. 

Many  natural  substances,  as  described  below^  are  used  either  di- 
rectly or  indirectly  in  the  manufacture  of  paints  and  coloring  mater- 
ials of  all  kinds.  The  product  may  be  marketed  as  ready  mixed  paint, 
as  a  powder  or  as  a  solid  material,  as  white  lead.  Ground  slates  and 
shales  are  used  as  fillers  in  oil  cloth  and  linoleum  manufacture,  as  well 
as  in  paints. 

Properties  and  ores. 

The  three  ores  of  iron,  hematite,  limonite  and  siderite,  are  the  basis 
from  which  the  metallic  paints  and  mortar  colors  are  derived. 
Limonite,  containing  more  or  less  clay,  forms  the  yellow  ochre  of 
commerce.  Metallic  paints  are  made  by  grinding  the  natural  oxides 
or  by  roasting  the  carbonate,  siderite.  Mortar  colors  are  used  for 
tinting  mortar,  cement  and  concrete. 

The  above,  together  with  umber,  sienna  and  ground  slate  and  shale, 
comprise  the  natural  mineral  pigments. 


COMMERCIAL    MINERALS   OF    CALIFORNLV,  63 

Umber  consists  of  iron  and  aluminum  silicates  with  varying  amounts 
of  manganese  oxides.  The  raw  material  is  drab  in  color,  but  after 
calcining  it  is  reddish  brown  and  is  called  'burnt  umber.'  Sienna 
is  essentially  the  same  composition  as  umber,  but  with  less  manganese 
oxide  and  is  a  lighter  color.  The  calcined  product  is  called  'burnt 
sienna. ' 

Pigments  which  are  manufactured  directly  from  ore.s  are  zinc  oxide, 
leaded  zinc  oxide,  white  lead  and  blue  lead. 

Pigments  which  are  entirely  chemically  manufactured  are  red  lead, 
A^^netian  red,  lithopone,  litharge  and  orange  mineral. 

Distribution. 

In  1917,  mineral  paint  was  produced  in  Calaveras,  Colusa.  San 
Bernardino  and  Stanislaus  counties.  That  from  Colusa  and  San  Ber- 
nardino was  hematite  and  jasper,  while  that  from  Calaveras  and  Stan- 
islaus Avas  yellow  ochre,  the  latter  product  being  of  excellent  quality 
and  the  equal  of  any  that  is  imported.  Deposits  of  mineral  paint 
are  also  located  in  Kern,  Kings,  Lake,  Los  Angeles,  Nevada,  Riverside 
and  Sonoma  counties. 

Tests. 

Deposits  of  material  suitable  for  mineral  paints  must  be  judged  as 

to   their   commercial   quality   by   persons   experienced   in   those   lines. 

Tests  for  and  descriptions  of  the  iron  ores  were  given  under  that 

heading. 

MOLYBDENUM. 

Molybdenum,  although  regarded  as  one  of  the  rarer  metals,  has 
recently  become  of  increased  value  on  account  of  its  use  in  the  steel 
industry.  The  United  States  at  present  appears  to  be  the  world's 
largest  producer,  and  exports  considerable  metal  and  concentrates. 
Arizona  and  Colorado  are  the  principal  producers.  In  1917  the  domes- 
tie  production  amounted  to  175  tons  of  metal,  valued  at  $^350,000. 
Xo  production  in  California  was  reported  up  to  1915.  In  that  year 
a  small  tonnage  was  mined  in  Plumas  County,  but  not  marketed.  In 
1916  there  were  8  'tons  of  picked  concentrate  produced  in  Inyo  and 
Plumas  County,  valued  at  $9,945.  In  1917  the  production  was  228 
tons  of  ore,  valued  at  $6,014.  There  was  only  one  producer  in  1918, 
a  flotation  plant  on  the  Boulder  Creek  mine  in  Shasta  County. 

The  price  has  increased  from  an  average  of  50^  per  pound  in  1914 
to  75^  per  pound  in  1916,  and  $1.00  per  pound  in  1917.  Occasionally 
quotations  have  been  as  high  as  $2.00  per  pound  of  90%  MoS,>.     The 


64  CALIFORNIA   STATE   MINING  BUREAU. 

quotation  at  San  Francisco  on  June  18,  1918  was  $1.25  per  pound 
for  90%  MoS,. 

Production  up  to  the  present,  has  been  limited  mainly  to  high 
grade  deposits,  but  it  is  hoped  that  the  more  stable  demand  will  lead 
to  the  concentration  of  the  ores  at  some  of  the  larger  deposits. 

Industrial  application  and  uses. 

The  importance  of  molybdenum  as  a  valuable  alloy  metal  appears 
now  to  be  well  established.  It  is  a  substitute  for  tungsten  in  the  manu- 
facture of  steel  for  certain  purposes,  and  in  this  regard  one  ton  of 
molybdenum  replaces  more  than  two  tons  of  tungsten.  About  15  to 
20  tons  of  metal  are  used  per  year  in  making  chemicals.  Most  of  the 
export  goes  to  our  allies  for  the  manufacture  of  high-speed  tool-steel, 
rifle  barrels,  propeller  shafts,  etc.  This  steel  contains  from  6  to  10% 
molybdenum.  It  is  also  used  with  tungsten  in  making  electric  light 
filaments,  and  electric  furnaces. 

Properties  and  ores. 

The  commercial  ore  of  molybdenum  is  molybdenite.  Composition 
(MoSo),  59%  molybdenum  and  41%  sulphur.  Light  bluish  gray  in 
color,  streak,  or  powder,  lead  gray  with  greenish  cast.  Occurs  in  scales 
or  hexagonal  plates,  or  foliated  masses.  Perfect  basal  cleavage. 
Hardness  1.0-1.5.  Gravity  4.7.  Crystallizes  in  the  hexagonal  system., 
Thin  plates  are  very  flexible,  but  not  elastic.  Resembles  graphite, 
but  slightly  different  in  color. 

Some  wulfenite  (molybdate  of  lead)  has  also  been  sold  for  the 
molybdenum  oxide  it  contained.  This  is  a  yellow,  orange,  or  bright 
red  mineral  with  resinous  or  adamantine  luster.  Occurs  massive  or 
in  thin  tabular  crystals.  Hardness  3.0-4.5.  Gravity  6.0-7.0.  To  be- 
marketable,  it  must  be  free  from  impurities  such  as  copper,  tungsten, 
vanadium,  chromium  and  contain  at  least  25%  of  molybdenum  oxide. 

Distribution. 

The  Sulphide,  molybdenite,  is  widely  distributed  in  California," 
usually  as  thin  flakes  and  leaves,  sometimes  large  and  well  formed 
crystals  in  quartz  and  crystalline  rocks,  and  contact  metamorphic 
deposits.  It  occurs  in  the  gold  quartz  veins  of  California.  In  appear- 
ance it  strongly  resembles  graphite,  but  has  a  lighter  bluish  lead-gray 
color.  When  occurring  alone  it  oxidizes  to  yellow  color,  and  occa- 
sionally to  peculiar  cobalt  blue  tinge.  It  has  been  found  in  the  Mother 
Lode  counties  and  in  Fresno,  Inyo,  Madera,  Mono,  Napa,  San  Diego, 
Shasta,  Tulare  and  Riverside  counties. 


COMMERCIAL   MINERALS  OF   CALIFORNIA.  65 

Tests. 

If  a  fragment  of  molybdenite  is  heated  before  the  oxidizing  flame 
of  the  blowpipe,  on  a  flat  charcoal  surface  for  some  time,  there  results 
a  short  distance  awaj^  a  coating  of  molybdic  oxide  (M0O3),  which 
is  pale  yellow  when  hot,  almost  white  when  cold  and  often  shows 
delicate  crystals.  Still  nearer  to  the  mineral  the  charcoal  is  covered 
with  a  very  thin  copper  colored  coating  of  M0O2  which  is  seen  best 
when  cold.  The  yellow  (M0O3)  coating  if  touched  for  an  instant 
with  the  reducing  flame  assumes  a  beautiful  ultramarine  blue  color, 
which  is  very  characteristic. 

This  same  yellow  coating  may  be  obtained  by  heating  a  fragment  of 
molybdenite  at  a  high  temperature  in  an  open  tube. 

If  a  small  piece  is  held  before  the  blowpipe  at  the  tip  of  the  blue 
flame,  a  pale  yellowish  green  color  is  imparted  to  the  flame. 

To  test  for  wulfenite,  put  a  very  small  portion  of  the  finely 
powdered  mineral  in  the  test  tube,  add  a  small  scrap  of  paper,  a  few- 
drops  of  water,  and  an  equal  quantity  of  concentrated  sulphuric  acid, 
and  heat  until  fumes  of  the  acid  begin  to  come  off.  Allow  to  become 
cold  and  add  water  a  drop  at  a  time.  A  deep  blue  color  appears 
which  vanishes  upon  the  addition  of  more  water.  For  success  in  this 
test  a  minute  quantity  of  the  powdered  mineral  should  be  used. 

Identification  of  Molybdenite. 

By  F.  C.  FuCHS.* 

A  small  piece  of  caustic  potash  is  melted  in  a  fragment  of  a  broken 
porcelain  dish  and  then  a  little  of  the  suspected  mineral  is  added. 
Within  five  minutes,  if  the  sample  is  molybdenite,  it  swells,  dissolves 
rapidly,  giving  the  mass  an  intense  red  yellowish  color,  and  not  a  single 
speck  of  the  brilliant  scaly  mineral  is  to  be  seen.  When  cool,  if  a 
few  cubic  centimeters  of  water  be  added  to  the  residue  of  fusion,  and 
afterward  some  drops  of  hydrochloric  acid,  the  color  begins  to  change 
and  in  spots  appear  the  blue,  green,  yellow  and  red. 

Metallurgy. 

Considerable  difficulty  has  been  experienced  in  the  concentration  of 
molybdenite  ore.  Until  quite  recently  the  world  markets  have  been 
supplied  by  cobbing  and  h^and  picking  the  ore  from  high  grade  de- 
posits. Some  wulfenite  ore  is  concentrated  as  this  is  amenable  to  the 
ordinary  jig  and  table  concentrating  processes. 

Within  the  last  few  years,  concentration  of  molybdenite  ore  by 
flotation,  with  either  water  or  oil,  and  by  electrositatic  processes  has 
been  to  some  extent  successful. 

♦Taken  from  issue  of  June  1,  1918,   of  Engineering  and  Mining  Journal. 

5—2484 


66  CALIFORNIA    STATE    MINING   BUREAU. 

Water  flotation  depends  solely  upon  the  fact  that  small,  dry  parti- 
cles of  molybdenite  float  upon  the  surface,  while  the  gangue  materials 
easily  become  wet  and  sink.  When  oil  is  added,  the  particles  of 
molybdenite  become  coated  with  oil  much  more  readily  than  the  gangue 
particles,  and  this  oil  coating  materially  assists  their  flotation.  In 
some  processes,  the  area  of  surface  of  flotation  is  increased  by  the 
liberation  of  air  or  gas  bubbles  in  the  liquid,  the  surface  of  each 
bubble  acting  in  the -same  way  as  the  surface  of  the  liquid.  These 
bubbles  may  be  produced  by  violent  agitation  of  the  pulp. 

It  has  been  found  by  experiments  that  no  general  method  is  appli- 
cable to  all  molybdenite  ores  and  each  individual  ore  has  its  own 
concentration  problems. 

Molybdenum  is  also  placed  on  the  market  in  the  form  of  a  powder 
made  by  heating  some  form  of  the  oxide  with  a  reducing  agent,  usually 
charcoal.  The  process  is  carried  on  in  graphite  crucibles,  and  the 
resulting  dark  powder,  commercial  molybdenum,  can  with  care,  be 
made  99%  pure. 

The  metal  may  also  be  prepared  by  passing  hydrogen  over  the  oxide 
at  a  red  heat. 

The  preparation  of  the  pure  oxide  is  rather  difficult.  This  is 
generally  done  by  roasting  the  sulphide  and  then  leaching  with  ammo- 
nium hydroxide.     Further  complex  treatment  is  required. 


MONAZITE. 

This  mineral  is  of  importance  because  it  is  a  source  of  some  of  the 
most  important  of  the  so-called    'rare  earth'    elements. 

The  United  States,  Brazil  and  India  have  produced  practically  all 
the  monazite  consumed,  while  Russia  and  Norway  furnish  small  quan-' 
tities.  The  production  in  the  United  States  comes  from  North  and 
South  Carolina.  The  placer  deposits  in  these  states  were  first  worked 
in  1886,  and  the  maximum  production  was  reached  in  1895  when 
1,573,000  pounds  of  monazite  sand  were  produced.  Imports  from  the 
rich  deposits  in  Brazil  lowered  domestic  production. 

There  has  been  no  production  in  California. 

Industrial  application  and  uses. 

The  rare  elements  cerium,  lanthanum,  thorium,  etc.,  which  are  gener- 
ally associated  with  each  other  in  the  mineral  monazite,  and  a  few 
others  are  used  commercially  in  the  form  of  their  nitrates  and  oxides 
only.  About  their  only  known  use  at  present  is  in  the  manufacture 
of  incandescent  gas  mantles. 


COMMERCIAL    MINERALS   OF    CALIFORNIA.  67 

The  mantle  is  made  of  fabric,  sueh  as  cotton,  and  impregnated 
with  the  nitrate,  which  when  dried  and  ignited  becomes  the  oxide, 
and  is  held  in  the  flame  by  means  of  fine  plaitinum  wire.  When 
heated  the  mantle  emits  an  intense  white  light.     Verj^  small  amounts 

('  used  in  some  searchlights,  automobile  headlights  and  flashlight 
!M»\vders. 

Properties  and  ores. 

^lonazite  in  composition  is  a  phosphate  of  cerium,  lanthanum,  and 
didymium  (CeLaDi)P04.  However,  it  carries  quite  a  per  cent  of 
thorium  and  is  the  only  mineral  found  in  the  United  States  from 
which  the  last  named  rare  metal  is  derived.  Uranium  and  radium 
may  also  be  present  in  minute  quantities.  The  common  form  of 
monazite  is  in  minute  crystals  or  granules,  disseminated  through 
uneissoid  or  pegnatitic  rocks,  and  owing  to  their  small  size  they  are 
generally  overlooked.  It  is  only  after  the  inclosing  rocks  are  decom- 
posvd  and  naitural  concentration  of  the  heavy  minerals  takes  place  that 
the  monazite  granules  are  found  in  the  resulting  sands. 

Distribution. 

Monazite  has  been  detected  in  California  in  some  of  the  black  sands, 
jind  in  the  concentrates  from  some  of  the  mines,  but  no  deposits  of 
commercial  size  are  known.  Its  presence  in  black  sands  has  been  re- 
ported from  Butte,  Del  Norte,  El  Dorado,  Humboldt,  Placer,  Plumas 
and  Yuba  counties. 

In  North  and  South  Carolina  monazite  is  obtained  by  washing 
the  sand  and  gravel  in  sluice  boxes,  in  the  manner  in  which  placer 
izold  is  washed. 

Tests. 

Dissolve  a  very  little  of  the  finely  powdered  mineral  by  heating  in  a 
test  tube,  Avith  a  few  drops  of  concentrated  sulphuric  acid.  When 
cool,  dilute  with  a  little  water,  filter  if  necessary  and  then  add  ammo- 
nium oxalate,  when  a  precipitate  of  the  rare-earth  metals  will  be 
formed. 


NATURAL  GAS. 

Natural  gas  ranks  as  one  of  the  state's  most  important  mineral 
pioducts. 

Outside  of  a  few  wells  in  Sacramento,  San  Joaquin  and  Kings 
counties  which  produce  gas  alone,  the  production  comes  mainly  from 
the  oil  producing  counties  of  the  state.  Practically  every  oil  well 
produces  some  gas,  but  it  is  not  always  possible  to  profitably  market  it. 


68  CALIFORNIA   STATE   MINING   BUREAU. 

Recently  ^reat  advancement  has  been  made  in  tapping  the  gas  at 
the  wells,  and  every  effort  is  now  being  made  to  conserve  the  supply. 
It  is  believed  the  figures  given  are  far  below  the  actual  production, 
because  of  many  w^ells  at  which  the  slight  flow  of  gas  cannot  be 
profitably  handled,  and  is  not  even  taken  account  of. 

As  in  the  case  of  oil,  Kern  County  leads  in  production  of  gas, 
almost  one-half  of  the  output  in  1918  being  accredited  to  this  county 
alone.  Orange  County  was  second.  Fresno,  Santa  Barbara,  Ventura 
and  Los  Angeles  are  important  producers. 

A  12-inch  pipe  line  is  operated  from  the  Midway  field  in  western 
Kern  County  to  Los  Angeles,  a  distance  of  107  miles.  Gas  is  also 
supplied  to  Bakersfield,  Taft,  Fellows  and  Maricopa. 

Gasoline  is  now  being  manufactured  by  at  least  50  plants  by  com- 
pression of  the  gas  which  accompanies  the  oil.  This  so-called  'casing- 
head'  gasoline  bids  fair  to  become  a  valuable  product.  The  produc- 
tion in  1918  from  all  fields  was  approximately  21,000,000  gallons. 

In  San  Joaquin  and  Sacramento  counties,  in  and  near  the  cities  of 
Stockton  and  Sacramento,  there  are  many  natural  gas  wells.  These 
wells  produce  a  good  quality  of  gas,  which  is  mixed  with  manufactured 
gas  for  domestic  use. 

Of  the  states.  West  Virginia  is  the  greatest  producer  of  natural 
gas.  In  1916  its  production  was  valued  at  $47,603,396,  while  the  total 
for  the  United  States  was  $120,227,468.  Pennsylvania  was  second, 
followed  by  Oklahoma  and  Ohio.     California  ranked  seventh. 

Prices  vary  considerably  in  the  different  states.  In  California  the 
average  price  per  thousand  feet  is  about  5^-8^. 


NICKEL. 

Practically  no  nickel-bearing  ores  are  mined  in  the  United  States, 
the  supply  for  many  years  having  come  from  Canada  in  the  form  of 
a  rich  copper-nickel  'matte,'"  from  which  the  refined  nickel  is  pro- 
duced. The  increased  demand  for  this  metal,  due  to  its  use  in  the 
manufacture  of  nickel  steel,  alloys  and  small  coins,  has  been  easily 
supplied  by  Canada,  for  in  the  past  more  was  received  than  was  re- 
quired for  domestic  use  and  the  balance  was  exported. 

The  proportion  of  nickel  coming  from  domestic  copper  ores  in  the 
electrolytic  refining  process  is  undetermined,  but  it  is  known  to  be 
small. 

Industrial  application  and  uses. 

The  most  important  use  for  nickel  at  present  is  in  the  manufacture 
of  nickel  steel.  This  contains  about  3.5%  nickel  and  is  used  for 
armor  plate  and  machines  requiring  great  strength. 


I 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  69 

For  man}^  years  nickel  has  been  used  as  one  in^edient  of  small 
coins.  Our  one  cent  piece  contains  about  12%  of  this  metal  and  the 
five  cent  piece  about  25%.  It  is  used  in  plating  other  metals  and 
alloys,  such  as  iron,  zinc  and  brass,  by  electrolysis.  Much  ornamental 
work  and  many  small  useful  household  articles  are  nickel-plated. 
So-called  'nickeloid'  is  nickel-plated  sheet  zinc.  Reflectors  and 
refrigerator  linings  are  often  made  of  nickel. 

Properties  and  ores. 

Nickel  is  a  pure  white  metal  with  bright  metallic  luster,  hard,  ductile 
and  tenacious.  It  takes  a  brilliant  polish  and  does  not  tarnish  in  the 
air. 

The  principal  ores  are  millerite,  pyrrhotite  and  niccolite. 

MiUerite  (NiS)  nickel  sulphide.  Contains  64.4%  nickel  and  35.6% 
sulphur.  A  valuable  ore  of  nickel.  Brass  yellow  to  bronze  in  color 
often  with  iridescent  tarnish,  greenish  black  streak,  metallic  luster, 
brittle,  quite  soft  (hardness  3.0-3.5)  and  heavy  (gravity  5.6).  Gener- 
ally occurs  as  coatings. 

PyrrJwtite  (Fe^Sg)  iron  sulphide.  Theoretically  contains  60.5% 
iron  and  39.5%  sulphur,  but  it  is  often  a  valuable  ore  of  nickel,  some- 
times containing  3  to  5%  or  more  of  this  metal.  Color  yellow,  bronze 
to  copper  red,  dark  grayish  black  streak,  brittle,  hardness  3.5-4.5, 
gravity  4.5,  slightly  magnetic,  and  tarnishes  easily. 

Niccolite  (NiAs)  Arsenical  nickel.  Also  called  copper  nickel  on 
account  of  its  color.  Contains  44%  nickel  and  56%  arsenic.  Pale 
copper  red  in  color,  metallic  luster,  pale  brownish  red  streak,  brittle, 
hardness  5.0-5.5,,  gravity  7.3-7.7.     Grenerally  occurs  massive. 

Occurrence. 

Nickel-bearing  pyrrhotite  occurs  in  the  Friday  Copper  mine  in  the 
Julian  District,  San  Diego  County.  Some  ore  was  mined  in  1915  and 
1916,  but  not  yet  treated.  It  is  claimed  that  new  discoveries  have 
been  made  in  this  county  and  development  started.  Pyrrhotite  has 
also  been  found  in  Siskiyou  and  Madera  counties. 

Some  millerite  has  been  found  in  Calaveras,  Humboldt,  Napa,  Placer 
and  Plumas  counties,  but  only  in  small  quantities.  It  is  often  associ- 
ated with  copper  and  cobalt  ores. 

Tests. 

Nickel  is  usually  detected  by  the  color  it  imparts  to  the  borax  bead. 
In  the  oxidizing  flame  it  gives  a  violet  color  when  hot,  changing  to 
reddish  brown  when  cold.  Nickel  compounds  when  dissolved  in  nitric 
acid    (HNO3)    give   an   apple   green  solution   and  when  ammonia  is 


70  CALIFORNIA    STATE    MINING   BUREAU. 

added  a  pale  blue  color  results.  Pyrrhotite  when  heated  in  the  reduc- 
ing flame  of  the  blowpipe,  is  fuseti  to  a  magnetic  globule.  Niccolite 
when  intensely  heated  gives  off  arsenic  fumes. 

Metallurgy. 

The  ores  are  roasted  and  smelted  in  blast  furnaces,  a  'matte' 
resulting  which  is  a  sulphide  of  nickel,  copper  and  iron.  The  iron  is 
removed  in  converters,  leaving  a  product  containing  about  80%  nickel 
and  copper  and  20%  sulphur.  This  is  refined  and  the  nickel  and 
copper  separated,  (1)  by  smelting  in  a  blast  furnace  with  salt  cake 
and  coke,  (2)  by  crushing,  dead  roasting  and  reducing  in  a  reverbera- 
tory  furnace  by  charcoal,  (3)  by  dead  roasting  and  treating  with 
sulphuric  acid  and  water  gas. 


NITRATES. 

The  natural  nitrates  are  found  in  many  places  in  the  desert,  regions 
in  the  southern  part  of  California,  but  no  commercial  production  has 
as  yet  been  made.  For  some  time  the  principal  supply  of  soda  niter 
has  come  from  Chile  in  South  America,  the  saltpeter  deposits  of  that 
country  having  for  years  been  quite  famous.  Here  the  impure  nitrate 
or    '  caliche '    is  first  sorted  and  then  refined  before  being  marketed. 

The  chief  commercial  source  of  niter  or  potassium  nitrate  has  been 
France,  Sweden  and  Germany.  In  the  United  States  it  has  been  found 
in  caves  in  Kentucky,  Indiana,  and  some  of  the  Western  States. 

It  is  believed  that  the  origin  of  nitrate  deposits  is  due  to  the  nitrify- 
ing agencies  of  bacteria  acting  uj^on  organic  matter,  by  which  means 
the  nitrogen  is  converted  into  nitric  acid,  and  this  combines  with  the 
bases,  lime,  soda  and  potash. 

Industrial  application  and  uses. 

Soda  niter  or  CJtile  saltpeter  is  probably  the  most  widely  used  of 
all  fertilizers,  nitrogen  being  one  of  the  most  essential  constituents  in 
all  animal  and  vegetable  life.  It  is  also  used  in  making  nitric  acid 
and  in  the  artificial  manufacture  of  niter,  by  replacing  the  sodium 
with  potassium. 

Niter  is  used  in  making  gunpowder,  fulminating  powder,  and  for 
other  pyrotechnic  purposes;  in  the  manufacture  of  nitric  and  sulphu- 
ric acid;  and  in  a  few  cases  as  a  medicine. 

Properties  and  ores. 

There  are  three  nitrates  of  importance;  thovse  of  sodium,  potassium, 
and  calcium. 


COMMERCIAL    MINERALS   OF    CALIFORNIA.  71 

Soda  Niter  (NaNOg)  Nitrate  of  sodium  called  Chile  saltpeter. 
Contains  36.5%  soda  (NaO)  and  63.5%  nitric  anhydride  (NOJ. 
When  pure  it  is  a  white  translucent  salt,  but  in  nature  is  often  brown, 
yellow,  or  reddish.  Vitreous  luster,  soft,  hardness  1.5-2.0,  specific 
^n-'avity  2.24-2.29.  By  far  the  most  common  of  the  nitrates,  and 
occurs  as  incrustations,  massive  or  as  crystals  with  perfect  rhombohed- 
ral  cleavage. 

Xifcr  or  Saltpeter  (KNO..)  Nitrate  of  potassium.  Contains  46.5% 
potash  (K2O)  and  53.57c  nitric  anhydride  (NOJ.  Color  white, 
vitreous  luster,  soft,  liardness  2.0,  specific  gravity  2.1,  taste  salty  and 
cooling.  Occurs  as  incrustations,  silky  tufts  or  acicular  crystals,  on 
dry  and  protected  places.  Very  rarely  found  in  commercial  quantities 
in  the  United  States. 

Xifrocalcite  (Ca(N03)o.nH20).  Hydrous  nitrate  of  calcium. 
Color  white  or  gray,  sharp  bitter  taste.  Occurs  in  soft,  silky  tufts  or 
masses. 

Distribution. 

The  nitrates  can  only  exist  in  solid  form  in  dry,  arid  or  desert 
regions.  In  such  regions  they  are  common  as  crusts,  or  tufts  which 
are  tlie  result  of  evaporation  of  solutions.  They  have  been  found  in 
Inyo,  San  Bernardino  and  Riverside  counties. 

Tests. 

The  nitrates  may  often  be  distinguished  by  their  taste  and  appear- 
cuiee.  Potassium  nitrate  and  soda  niter  both  burn  vividly  when  thrown 
on  live  coals,  the  former  giving  a  violet  color  and  the  latter  the  yellow 
sodium  color.  The  soda  niter  deliquesces,  or  becomes  liquid,  upon 
exposure  to  damp  air.  When  heated  in  a  closed  tube,  or/ better,  a 
bulb  tube,  with  potassium  bisulphate,  all  nitrates  yield  NOo  gas  which 
may  be  detected  by  its  red  color. 

Preparation. 

In  Chile  the  crude  nitrate  or  'calicbe'  is  refined  by  crushing  and 
treating  with  boiling  water  in  tanks  heated  by  steam  coils,  until  it 
reaches  a  certain  density,  when  it  is  run  out  to  cool  and  crystallize. 
Certain  impurities  are  left  behind  and  the  process  is  repeated  until 
a  sufficiently  pure  product  is  obtained. 

Xiter,  or  saltpeter,  is  prepared  by  scraping  up  the  thin  coatings, 
or  deposits,  lixiviating  the  material  with  water  and  then  evaporating 
the  solution.     Potash  is  added  to  recover  the  calcium  nitrate. 


72  CALIFORNIA   STATE   MINING  BUREAU. 

PETROLEUM. 

The  United  States  is,  by  far,  the  greatest  producer  of  petroleum 
in  the  world,  the  annual  production  being  more  than  four  times  that 
of  its  nearest  competitor,  Russia.  Mexico,  the  Dutch  East  Indies, 
Galicia,  India  and  Rumania  are  also  important  producing  countries. 
The  production  in  the  United  States  for  the  last  few  years  has  been 
around  300,000,000  barrels  annually. 

The  total  production  in  California,  since  discovery,  is  greater  than 
the  total  production  of  any  other  state,  for  an  equal  period. 

For  many  years,  from  1903  to  1914  inclusive,  with  the  exception 
of  two  years,- 1907  and  1903,  California  lead  all  the  states  in  annual 
production.  For  those  two  years  Oklahoma  showed  a  greater  pro- 
duction, and  since  1914  it  has  been  the  leading  state,  with  California 
a  very  close  second. 

The  industry  in  this  state  is  described  in  detail  in  Bulletin  No.  69, 
issued  by  the  State  Mining  Bureau,  entitled  "The  Petroleum  Industry 
of  California."  This  bulletin  is  accompanied  by  a  folio  of  geological 
maps  of  the  oil  fields.  The  annual  reports  of  the  State  Oil  and  Gas 
Supervisor,  Bulletins  Nos.  73,  82  and  84  respectively,  and  Bulletins, 
3,  11,  16,  19,  31,  32,  63,  contain  much  valuable  information  relative 
to  the  industry. 

The  following  brief  data  is  taken  from  recent  reports : 

There  are  89,212  acres  of  proved  oil  land  in  California,  cf  which 
57,499  acres  are  in  Kern  Count}^  Fresno  County  ranks  second,  with 
13,319  acres.  Other  counties  with  acreages  are:  Santa  Barbara,  9363; 
Orange,  3530;  Los  Angeles,  2873;  Ventura,  1776;  San  Luis  Obispo, 
772;  Santa  Clara,  80. 

Tbe  Midway-Sunset  field  in  western  Kern  County  has  been,  by 
quite  a  margin,  the  largest  producing  district,  although  about  the  same 
number  of  wells  are  operated  in  the  Kern  River  field  near  Bakersfield 
in  the  same  county. 

The  average  price  for  the  whole  state  has  increased  from  47.9^  in 
1915  to  63.6^  in  1916,  90.8^  in  1917,  and  $1.24  in  1918. 

The  production  in  California  in  1918  was  99,731,177  barrels,  valued 
at  $127,459,221. 

PHOSPHATE  ROCK. 

The  United  States  produces  approximately  one-half  of  the  world's 
output  of  phosphate  rock.  The  greatest  deposits  are  located  in  Flor- 
ida, South  Carolina,  Tennessee,  Kentucky,  Arkansas,  Wyoming,  Idaho 
and  Utah.  Florida  produces  about  76%  of  the  total.  No  deposits 
of  commercial  value  have  been  located  in  California. 


I 


COMMERCIAL   MINERALS  OP   CALIFORNIA.  73 

Industrial  application  and  uses. 

Phosphate  rock  is  used  almost  entirely  as  a  fertilizer.  Phosphorus, 
togrether  with  nitrogen  and  potash,  comprise  the  fertilizing  materials 
that  are  essential  to  continuous  producing  soil.  The  phosphate  rock 
is  finely  ground  and  used  directly  as  a  fertilizer,  or  it  is  treated  with 
sulphuric  acid  in  the  production  of  super-phosphate.  Due  to  its  con- 
tent of  phosphoric  acid  it  is  used  in  certain  chemicals. 

Properties  and  ores. 

Phosphate  rock  is  a  sedimentary  deposit  containing  calcium  phos- 
phate. It  is  a  hard  rock  found  in  beds  between  layers  of  sandstone, 
shale,  or  other  sedimentary  rock ;  in  stream  deposits ;  or  as  a  residuum 
from  the  decomposition  of  limestone,  dolomite  or  other  rocks  containing 
phosphate. 

Apatite  (CaF)Ca4(P04)3,  a  fluoride  of  calcium,  with  fluorine  and 
sometimes  chlorine,  is  also  a  commercial  source  of  phosphoric  acid. 
In  color  it  may  be  brown,  green,  yellow  or  pink,  vitreous  or  greasy 
luster,  hardness  5.0,  specific  gravity  3.17-3.23.  Occurs  massive  or 
granular. 

Monazite  is  a  phosphate  of  the  rare  earth  minerals  cerium,  lan- 
thanum, didymium  and  thorium,  and  is  a  source  of  these  minerals. 

Distribution. 

No  commercial  bodies  of  phosphate  rock  have  as  yet  been  located  in 
California.  Apatite  has  been  found  as  crystals  in  many  of  the  rocks 
of  the  state. 

The  phosphate  reserves  in  the  United  States  are  estimated  to  be 
6,000,000,000  tons.  Great  areas  of  high  grade  material  in  the  western 
states  have  been  examined  and  classified. 

Tests. 

When  a  cold  or  slightly  warm  nitric  acid  solution  of  a  phosphate 
is  added  to  a  solution  of  ammonium  molybdate  a  yellow  precipitate  is 
formed.  This  is  a  delicate  test.  Only  a  small  amount  of  the  phos- 
phate solution  should  be  added  at  first,  as  the  precipitate  will  not 
form  in  an  excess  of  phosphoric  acid.  This  test  may  be  made  on  the 
phosphate  mineral  itself  by  moistening  with  a  drop  of  nitric  acid  and 
then  applying  a  crystal  of  ammonium  molybdate,  when  the  yellow 
color  will  spread  over  the  mineral.  Many  phosphates  when  heated 
before  the  blowpipe,  or  when  moistened  with  concentrated  sulphuric 
acid  and  then  heated,  give  a  pale  bluish-green  color  to  the  flame. 


74  CALIFORNIA    STATE    MINING   BUREAU. 

PLATINUM. 

The  United  States  before  the  war  apparently  used  about  165,000 
fine  ounces  of  platinum  per  year.  The  imports  for  several  years  prior 
to  1914,  averaged  around  118,000  troy  ounces.  The  domestic  pro- 
duction was  very  small,  approximately  600  to  800  ounces  yearly. 
Considerable  platinum  is  recovered  from  the  refining  of  blister  copper, 
and  much  secondary  metal  is  derived -from  refining  scraps  and  sweep- 
ings. The  imports  have  steadily  decreased  for  the  last  few  years  until 
in  1917  they  were  only  about  one-fourth  of  the  pre-war  figure.  Cali- 
fornia is  the  largest  producer  in  the  United  States.  In  1918  the  pro- 
duction from  this  state  was  571  ounces  of  crude  platinum-group 
metals,  valued  at  $42,788. 

In  the  past  about  95%  of  the  world's  supply  has  come  from  the 
Ural  Mountains  in  Kussia,  but  this  supply  has  been  cut  down  about 
one-third  in  the  last  two  years.      Columbia  is  the  next  largest  producer. 

In  1915  California  miners  received  from  $28  to  $38  per  ounce  for 
crude  platinum.  In  1916  this  had  increased  to  from  $43  to  $76  per 
ounce.  The  quotation  on  the  pure  inetal  was  often  over  $100  per 
ounce  in  1916  and  1917.  I 

Industrial  application  and   uses. 

Platinum  in  the  form  of  wire,  foil,  crucibles,  and  dishes  of  various 
shapes    and    sizes,    is    absolutely    necessary   in    chemical    laboratories. 

Upon  such  laboratories  all  great  industries  depend  for  guidance. 
It  has  wide. application  in  instruments  of  precision,  and  in  the  electri- 
cal industry,  telegraph  and  telephone  apparatus,  etc.  At  present  one 
of  its  most  important  uses  is  in  the  contact  process  of  making  con- 
centrated sulphuric  acid.  As  a  war  metal  its  alloys  with  iridiunij 
osmium,  and  the  allied  metals  are  needed  for  electrical  equipment  on 
aeroplanes,  trucks,  tractors,  and  instruments  used  by  the  signal  and 
medical  corp.  For  many  of  the  delicate  parts  mentioned  above, 
there  is  no  substitute  for  platinum.  Considerable  amounts  are  used 
in  dentistry  and  in  the  making  of  jewelry. 

Properties  and  ores. 

Pure  platinum  (Pt.)  is  a  lustrous,  grayish-white  metal,  quite  mal- 
leable and  ductile.  Hardness  4.0-4.5.  Gravity  14.0-19.0,  very  heavy. 
Generally  occurs  in  small  grains  or  nuggets  of  a  size  to  pass  a  twenty- 
mesh  screen,  associated  with  gold-bearing  placers.  It  has  not  yet 
been  found  in  place  in  California,  hence  has  not  been  detected  as  a  con- 
stituent of  the  rocks,  but  its  origin  no  doiibt  lies  in  the  basic  igneous 
rocks  which  alter  to  serpentine.  It  has  been  found  in  such  associations 
in  Russia  and  in  British  Columbia.     Crude  platinum  is  generally  an 


COMMERCIAL   MINERALS   OP   CALIFORNIA.  75 

alloy  of  from  ol'/^    to  85%   platinum,  the  remainder  being  iridium, 
osmium,  and  the  allied  rarer  metals. 

Considerable  platinum  is  now  recovered  in  the  electrolj'tie  refining 
of  blister  copper.  It  has  been  found  that  this  product  often  carries 
from  0.34  to  1.8  ounces  of  platinum  and  from  0.6  to  4.4  ounces  of 

•  palladium  per  100  tons  of  blister  copper  treated. 

Distribution. 

4  The  characteristic  occurrence  of  platinum  in  California  is  in  metallic 
I  grains  associated  with  the  gold-bearing  black  sands  of  the  stream 
I  beds,  placers  and  beach  sands.     It  is  found  in  a  great  many  localities, 

*  and  the  greatest  amount  is  recovered  by  the  many  gold  dredges  now 
in  operation,  principally  in  Yuba,  Sacramento,  Butte  and  Calaveras 
counties.  Hydraulic  and  surface  sluicing  mines  in  Del  Norte,  Hum- 
boldt, Siskiyou  and  Trinity  counties  have  yielded  considerable  amounts. 
^Merced.  Stanislaus,  Nevada  and  Shasta  counties  are  smaller  producers. 

Tests. 

Distinguishing  qualities  are  its  malleability,  high  specific  gravity, 
extreme  infusibility  and  insolubility  in  any  single  acid.  It  can  be 
dissolved  in  aqua  regia,  a  mixture  of  3  parts  of  hydrochloric  acid 
and  1  part  nitric  acid.  It  will  not  amalgamate  with  quicksilver  alone, 
Init  will  amalgamate  if  sodium  is  added.  Simple  tests  are  as  follows: 
Dissolve  in  aqua  regia  and  evaporate  to  dr\'ness.  Dissolve  again  in 
i  ydroehloric  acid  alone,  and  evaporate  until  thick,  but  not  quite  dry. 
Add  distilled  water,  a  few  drops  of  sulphuric  acid,  and  potassium 
iodide  solution.  In  the  presence  of  platinum  a  wine  red  color  will 
result.  Potassium  chloride  or  ammonium  chloride  will  give  a  yellow 
precipitate. 

To  test  black  sand,  put  a  small  amount  in  a  test  tube,  add  hydro- 
chloric acid  and  nitric  acid  in  the  ratio  of  2  to  1,  warm  for  a  few 
minutes,  pour  out  this  solution  and  again  add  acid  in  same  ratio  and 
boil.  Pour  what  remains  of  the  solution  over  a  filter  paper  and  then 
add  stannous  chloride.  An  orange  color  will  appear  if  platinum  is 
]^ resent.     Gold  gives  a  red  purple  or  brown  purple  color. 

Metallurgy.  \ 

The  metal  is  obtained  from  the  gravel  and  sand,  by  classification, 
concentration  and  amalgamation  with  electrol.vtic  sodium  amalgam. 
Within  recent  years  the  dredging  and  hydraulic  mining  companies 
have  given  close  attention  to  saving  the  platinum,  and  the  above 
method  is  the  one  in  general  use. 


76  CALIFORNIA   STATE   MINING  BUREAU. 

Albert  H.  Sherwood  of  Oroville  has  patented  a  process  for  the  re- 
covery of  fine  gold  and  platinum,  in  which  the  sands  are  treated  with 
an  acidulated  solution  of  copper  sulphate,  the  platinum  particles 
becoming  copper  plated  after  which  their  amalgamation  with  ordinary 
amalgam  is  a  simple  matter. 


POTASH. 

Before  1915  the  United  States  was  almost  wholly  dependent  upon 
Germany  for  its  potash  supply.  The  normal  annual  importation  be- 
fore the  war  was  about  250,000  short  tons  (reckoned  as  K2O)  with  a 
value  around  $15,000,000.  This  represented  over  1,000,000  tons  of 
all  classes  of  potash  material.  There  was  practically  no  domestic 
production. 

In  1916  and  1917  the  imports  were  reduced  to  about  3000  tons  K^O. 
The  demand  "had  increased  to  a  great  extent  during  this  period,  due 
to  its  use  in  the  manufacture  of  powder,  signal  rockets,  fertilizer,  etc. 
The  country  was  therefore  suddenly  thrown  upon  its  own  resources 
in  this  regard.  The  1916  production  was  not  very  encouraging,  the 
principal  output  being  from  California,  which  produced  17,908  tons 
valued  at  $663,605.  However,  in  1917  the  output  of  this  state  in- 
creased to  138,760  tons  valued  at  $4,098,106. 

Prices  for  German  potash  salts  delivered  in  the  United  States,  before 
the  war,  ranged  from  $8.25  for  12|%  K.O  to  $38  per  ton  for  material 
containing  50%  K2O. 

In  1917  it  is  estimated  that  50%  K.O  brought  $213  per  ton. 

Industrial  application  and  uses.  ' 

Potash  is  used  principally  as  a  fertilizer  and  for  some  crops  its 
application  is  now  regarded  as  essential.  It  enters  into  the  manufac- 
ture of  nearly  all  explosives,-  fireworks,  etc.,  as  saltpeter  (potassium 
nitrate).  Ordinary  black  powder  is  75%  saltpeter.  In  the  manufac- 
ture of  matches,  potassium  chlorate  is  extensively  used.  Other  numer- 
ous uses  are  in  the  manufacture  of  soap  and  glass,  and  in  dyeing, 
tanning  and  metallurgy. 

Properties  and  ores. 

Potassium  (K)  is  the  basis  of  all  potash  salts  or  compounds.  It 
is  a  soft,  silver  white  metal,  so  light  that  it  floats  upon  water,  its 
specific  gravity  being  0.86.  It  has  a  brilliant  metallic  luster  which 
soon  disappears  in  the  air,  owing  to  rapid  oxidization.  It  is  therefore 
usually  seen  covered  with  a  grayish  coating  and  must  be  kept  under 
oil.     In    combination    with   oxygen    it    forms    potassium    oxide,    K^O, 


mm  COMMERCIAL   MINERALS   OF   CALIFORNIA.  77 

known  as  potassa,  but  commonly  called  'potash,'  because  it  was  first 
prepared  by  evaporating  the  solution  of  ashes  in  iron  pots,  hence  *  pot- 
ash.'  The  material  thus  obtained  was  an  impure  potassium  carbon- 
ate (K0CO3),  a  white  powder  which  absorbs  moisture  from  the  air, 
and  is  very  soluble  in  water,  and  has  a  strong  alkaline  reaction.  The 
term  was  afterwards  used  to  include  'caustic  potash'  (KOH)  com- 
monly known  as  lye,  which  is  produced  by  treating  potassium  car- 
bonate with  lime  (CaO).  The  form  K._.0  is  now  commonly  used  as  a 
standard  in  speaking  of  potash  products. 

Potash  salts  are  generally  sold,  however,  as  potassium  sulphate 
(K2SO4),  potassium  chloride  or  'muriate'  (KCl),  potassium  nitrate 
(KNO,).  and  potassium  carbonate  (K0CO3).  Potassium  chloride 
closely  resembles  common  salt  (NaCl)  in  color,  taste,  etc. 

Potassium  nitrate  is  also  called  'niter'  or  'saltpeter.'  It  is  a 
white  .^olid,  which  dissolves  readily  in  water.  At  high  temperature  it 
gives  off  oxygen  easily,  and  this  led  to  its  extensive  use  in  explosives, 
matches,  etc.     Potassium  sulphate  is  used  principally  as  a  fertilizer. 

The  principal  sources  from  which  potash  has  been  produced  are  from 
natural  salts  and  brines,  silicate  rocks,  furnace  dust,  kelp,  wood  ashes, 
distillery  waste  and  miscellaneous  organic  sources.  Alkali  lakes,  prin- 
cipally in  western  Nebraska  and  California,  have  furnished  the  most 
readily  available  supply  and  the  largest  output.  Great  progress  has 
been  made  in  the  last  few  years  in  the  extraction  of  potash  from  kelp. 

Distribution. 

h^  At  Searles  Lake  in  San  Bernardino  County  there  is  a  great  deposit 
"of  potash  salts  and  a  less  important  one  at  Owens  Lake,  Inyo  County. 
Active  operations  are  in  progress  at  both  of  these  deposits.  Around 
Los  Angeles  and  San  Diego,  during  1915-1918,  several  companies 
extracted  potash  from  kelp.  It  is  estimated  that  there  are  225  square 
miles  of  commercially  valuable  beds  of  kelp  along  the  coast  of  South- 
ern California.  The  raw  or  wet  kelp  yields  10%  dry  material  and  this 
latter  contains  about  12%  K^O.  At  Riverside,  Victorville  and  Santa 
Cruz  potash  is  recovered  as  a  by-product  in  the  manufacture  of  cement. 

Tests. 

Volatile  potassium  compounds  when  heated  in  a  non-luminous  (blue) 
flame,  such  as  given  by  an  alcohol  lamp  or  blowpipe,  will  produce  a 
characteristic  violet  color.  The  test  to  be  made  with  a  little  of  the 
solution  of  the  mineral  on  a  clean  platinum  wire.  Before  testing 
dip  the  wire  in  hydrochloric  acid  and  lieat.  Organic  substances  may 
be  burned  and  the  ashes  tested  in  this  way. 


78  CALIFORNIA   STATE    MINING   BUREAU. 

PUMICE   AND   VOLCANIC   ASH. 

For  many  years  the  principal  supply  of  commercial  pumice  has 
come  from  the  Lipari  Islands,  off  the  coast  of  Italy.  This  supply 
has  in  the  past  few  years  been  largely  shut  off.  Deposits  of  commer- 
cial value  of  pumice  and  volcanic  ash  have  been  found  in  this  country 
in  California,  Kansas,  Nebraska  and  other  states. 

Industrial  application  and   uses. 

Pumice  is  used  as  a  polishing  and  scouring  material,  and  volcanic  ' 
ash  is  used  in  the  manufacture  of  scouring  soaps  and  polishing  pow-  , 
ders.     Pumice  is  used  to  a  great  extent  by  painters  for  smoothing  and 
polishing  surfaces  of  carriages,  automobiles,  etc.,  or  any  surface  that 
requires  an  excellent  finish. 

Recently,  light  volcanic  material  of  sufficient  strength  has  been  tested 
for  use  as  aggregate  in  concrete  for  ship-building. 

Properties. 

Pumice  is  a  glassy  volcanic  rock,  which  has  a  very  porous  or  scoria- 
ceous  structure  due  to  the  expansion  of  gases  and  vapor,  while  in  a 
molten  state.  It  is  light,  spongy  and  froth-like  in  appearance,  white 
or  gray  in  color,  hard  and  brittle.  The  cutting  or  abrasive  quality 
is  due  to  the  thin  partitions  of  glass  composing  the  walls  between  the 
vesicles. 

Volcanic  a.sh  is  material  of  a  much  finer  nature,  being  broken  and 
powdered  by  volcanic  explosions.  Both  are  in  general  of  rhyolitic 
or   andesitic   composition. 

Distribution. 

During  the  summer  of  1917  inquiry  was  made  by  the  State  oMining 
Bureau*  regarding  the  location  of  deposits  of  pumice,  volcanic  ash 
and  vesicular  lava  in  this  state. 

There  is  an  extensive  deposit  of  coarsely  porous  pumice  in  eastern 
Siskiyou  County  which  has  been  tested  in  concrete  which  was  to  be 
used  for  heat  insulation.  It  gave  a  very  light  concrete  with  superior 
heat-resisting  qualities,  but.  too  low  in  compressive  strength  to  be  of 
use.  More  recently,  another  deposit  of  finer  grained  block  pumice 
has  been  opened  in  this  same  district,  and  several  hundred  tons  are 
said  to  have  been  shipped  during  1918  to  the  east.  This  pumice  has 
been  tested  in  concrete  and  i-ave  a  product  light  enough  to  float  half 
submerged  in  water.  This  concrete  was  probably  strong  enough  for 
ordinary  construction  requirements,  but  could  not  meet  the  high 
strength   standard   set   for   concrete   shipbuilding.     It   is   quite  likely 


♦By  C.  A.  Logan,  Field  Assistant. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  79 

that  piunice  may  soon  come  into  use  as  an  aggregate  in  concrete  where 
light  weight  is  desired  and  moderate  strength  is  sufficient,  as,  for 
example,  in  small  buildings,  floors  and  partitions.  Its  fireproof  and 
heat-insulating  properties  would  make  it  attractive  for  such  uses. 
Experimental  work  in  this  direction  has  been  discouraged  by  high 
cost  of  transportation  from  the  known  deposits  to  centers  of  population. 
Volcanic  ash  or  tuff  is  widely  distributed  in  California,  large  deposits 
of  fair  quality  being  found  near  transportation  in  Napa,  Madera,  San 
^  Luis  Obispo,  and  other  counties,  particularly  in  the  southeastern  desert 
region.  Besides  its  industrial  uses,  tliis  ash,  when  sufficiently  con- 
solidated by  natural  agencies,  has  been  found  suitable  for  building 
small  bridges  and  buildings  and  for  road  material  in  the  localities 
where  it  occurs.  Some  samples  of  such  tuff  gathered  by  the  State 
Alining  Bureau  last  summer  showed  great  compressive  strength  and 
very  light  weight,  but  have  not  been  thoroughly  tested  in  concrete. 

Vesicular  Ir\r  from  California  has  been  tested  as  aggregate  in  con- 
crete and  gave  a  product  possessing  great  compressive  strength  and 
weighing  only  about  two-thirds  as  mucli  as  ordinary  concrete.  Un- 
fortunately our  deposits  of  this  rock  near  transportation  are,  so  far 
as  known,  confined  to  the  desert  regions  from  ^lono  Lake  southw^ard. 
In  Imperial  County  there  is  a  deposit  of  vesicular  block  pumice,  which 
has  found  a  ready  market. 

Tests. 

This  class  of  material  is  easily  distinguished  by  its  physical  proper- 
ties, especially  its  porous,  vesicular  structure,  and  its  lightness.  The 
deciding  factors  as. to  whether  or  not  a  deposit  is  of  commercial  value 
are  nearness  to  transportation,  lightness  and  strength. 


PYRITES. 
Industrial  application  and  uses. 

Pyrites  are  used  mainly  for  the  manufacture  of  sulphuric  acid. 
There  are  two  classes — lump  and  fines — the  lump,  commanding  some- 
what higher  prices.  For  commercial  value  the  sulphur  content  should 
be  over  40%  and  very  few  of  the  acid  companies  wall  accept  material 
that  carries  less  than  35%  sulphur.  Certain  elements  such  as  arsenic 
and  antimony  are  harmful,  and  also  carbonaceous  material  is  objection- 
able. Low-grade  acid  made  from  impure  pyrites  is  used  in  fhe  manu- 
facture of  fertilizers. 

Properties  and  ores. 

The  term  pyrites  is  the  general  trade  name  for  the  several  iron 
sulphide  minerals  such  as  pyrite,  marcasite,  and  pyrrhotite. 


80  CALIFORNIA   STATE   MINING  BUREAU. 

Pyrite  and  marcasite  (FeSg)  have  identical  chemical  composition 
and  when  pure  contain  about  47%  iron  and  53%  sulphur.  They 
differ,  however,  in  crystallization. 

Pyrite  is  pale  brass-yellow  in  color,  streak  black  to  brownish  or 
greenish,  metallic  luster,  hardness  6.0-6.5,  specific  gravity  6.0.  Gen- 
erally found  in  cubes  or  octahedrons.  It  is  the  most  common  of  the 
sulphide  minerals  and  is  found  in  all  kinds  of  rocks,  but  is  more 
prominent  in  metamorphic  schists,  slates,  etc.  and  in  unaltered  sand- 
stones. Common  in  gold  districts,  and  it  is  from  pyrite  bodies  that 
most  of  the  copper  production  of  the  state  is  obtained. 

Marcasite,  called  white  pyrites,  is  pale  yellow  to  almost  white  in 
color,  with  black  somewhat  grayish  streak,  metallic  luster,  hardness 
6.0-6.5,  specific  gravity  4.85-4.9.  Commonly  in  tabular  crystals,  also 
massive.  Cannot  be  easily  distinguished  from  pyrite,  except  when  in 
crystals.  Much  more  rare  than  pyrite  and  characteristically  associated 
with  clays  and  cinnabar. 

Pyrrhotite  (Fe^S^)  or  (Fe^Sis)  or  (FcnS.n+i)  Magnetic  pyrite.s. 
Color  brown  or  bronze,  streak  grayish  black,  metallic  luster,  hardness 
3.5-4.5,  specific  gravity  4.58-4.64.  Usually  slightly  magnetic.  Com- 
monly massive,  granular  or  compact,  sometimes  in  large  lenticular 
masses.  Associated  w^ith  pyrite.  Found  in  gold  and  copper  districts, 
and  often  carries  nickel.  Masses  occur  in  serpentine  and  pegmatite 
veins. 

Occurrence. 

In  1918  pyrite  was  produced  in  Alameda,  El  Dorado  and  Shasta 
counties.  It  occurs  in  many  localities  in  other  counties,  but  not 
generally  in  such  quantity  or  quality,  or  not  so  economically  situated 
as  to  be  of  value  commercially. 

Tests. 

Pyrite  and  marcasite  when  heated  in  the  closed  tube  give  mucli 
sulphur.  Pyrrhotite  when  similarly  treated  gives  little  or  no  sulphur. 
All  are  magnetic  when  heated  before  the  blowpipe.  Pyrite  dissolves 
completely  if  a  little  of  the  very  fine  powder  is  treated  in  a  test  tube 
with  concentrated  nitric  acid.  It  should  be  allowed  to  stand,  cold, 
until  vigorous  action  ceases  and  then  boiled.  The  nitric  acid  should 
be  strong  enough  to  decompose  the  mineral  completely  before  heating. 
Marcasite  when  treated  as  above  yields  some  separate  sulphur.  Th( 
nitric  acid  solutions  of  iron  compounds  are  yellowish  in  color,  and 
when  ammonia  is  added  in  excess,  brow^nish  red  precipitates  of  ferric 
hydroxide  are  produced. 


COMMERCIAL   MIIS^RALS   OF   CALIFORNU.  81 

SULPHURIC  ACID. 

Sulphuric  acid  is  manufactured  by  bringing  together,  under  suit- 
able conditions,  sulphur  dioxide  (SOJ,  oxygen  (0)  and  water  (HgO), 
as  steam,  in  the  presence  of  certain  oxides  of  nitrogen.  The  latter 
simply  act  as  carriers  of  the  oxygen.  The  oxygen,  water  and  sulphur 
dioxide  combine  to  form  sulphuric  acid  (H2SO4),  but  the  reactions 
are  much  more  complicated  than  the  mere  union  of  these  substances. 


QUICKSILVER  OR  MERCURY. 

California   produces   about   75%    of   the   quicksilver  mined  in   the 
United  States.     The  production  in  1918  was  22,621  flasks,  valued  at 
i  $2,579,472. 

fndustrial  application  and  uses. 

By  far  the  greatest  consumption  is  in  the  manufacture  of  fulminate 
for  explosive  caps  and  in  drugs.  It  is  an  absolute  necessity  from  a 
military'  standpoint,  as  there  has  not  yet  been  found  a  substitute  for 
it  in  the  manufacture  of  fulminating  caps. 

In  the  recovery  of  gold  and  silver  the  mercury  is  placed  on  amal- 
gamation plates  both  inside  and  outside  the  stamps  and  collects  the 
fine  particles  of  gold. 

Ordinary  calomel  is  mercurous  chloride  (HgCl),  and  the  bichloride 
has  an  extensive  use  as  a  disinfectant.  Much  mercury  is  used  in 
scientific  apparatus,  such  as  thermometers,  barometers,  etc.,  and  in 
many  electrical  appliances. 

Properties  and  ores. 

Mercury  (Hg)  is  a  bright  silvery  metal,  distinguished  by  being  the 
only  one  which  is  liquid  at  ordinary  temperatures.  It  was  from  this 
fact  that  it  received  its  comman  name  of  quicksilver.  The  Latin 
name  from  which  the  symbol  Hg.  is  derived  means  literally  'water 
silver.'  It  is  very  heavy  (specific  gravity  13.59),  and  slightly  volatile 
at  ordinary  temperatures,  the  vapor  being  poisonous.  It  does  not 
tarnish  in  the  air  unless  sulphur  compounds  are  present. 

Cinnabar  (HgS),  sulphide  of  mercury  is  the  most  important  ore. 
Contains  86,2%  mercury  and  13.8%  sulphur.  Distinguished  by  its 
brilliant  red  color  and  adamantine  luster.  The  streak  is  scarlet  red. 
Quite  soft  (hardness  2.0-2.5)  and  very  heavy  (specific  gravity  8.0-9.0). 
Perfect  prismatic  cleavage.  Generally  occurs  massive  and  granular, 
but  small  crystals  are  common.  Globules  of  free  mercury  are  often 
found  with  the  cinnabar  in  many  of  the  mines. 


6-24S4 


82  CALIFORNIA   STATE   MINING  BUREAU. 

Metacinnaharite  (HgS),  the  black  sulphide  of  mercury,  has  the  same 
composition  as  cinnabar,  but  is  grayish  black  in  color,  has  a  black 
streak,  metallic  luster,  hardness  3.0,  specific  gravity  7.81.  Usually 
massive  and  amorphous.  Found  in  many  of  the  cinnabar  deptisits  in 
the  state. 

Distribution. 

Cinnabar  was  known  in  this  state  long  before  the  discovery  of  gold. 
The  .most  important  deposits  lie  in  the  Coast  Ranges,  extending  from 
Del  Norte  to  Santa  Barbara  County.  San  Benito  is  the  largest  pro- 
ducing county  followed  in  order  by  Santa  Clara,  San  Luis  Obispo, 
Napa,  Lake,  Sonoma,  Solano  and  Colusa  counties.  Small  quantities 
are  also  found  in  Kern,  Kings,  Monterey,  Santa  Barbara,  Stanislaus 
and  Trinity  counties.  The  New  Idria  Mine  in  San  Benito  County  is 
the  largest  producer  in  the  United  States.  The  other  producing  .states, 
are  Nevada,  Texas,  and  Arizona. 

Tests. 

Cinnabar  may  be  distinguished  by  its  brilliant  color,  streak  and 
luster.  The  most  satisfactory  test  is  the  formation  of  metallic  mercury 
when  heated  in  the  closed  tube  with  sodium  carbonate.  A  little  of 
the  powdered  mineral  is  mixed  with  about  four  volumes  of  dry  sodium 
carbonate,  placed  in  a  closed  tube,  covered  with  an  additional  layer 
of  sodium  carbonate  and  then  heated  gently.  Metallic  mercury  will, 
distill  off  and  collect  as  globules  on  the  sides  of  the  tube.  When 
heated  alone  in  the  closed  tube,  gives  a  black  sublimate  (HgS.)  Gives 
sulphur  dioxide  (SOo)  aud  free  mercury  when  heated  in  the  open 
tube. 

Metallurgy. 

Mercury  is  obtained  from  its  ores  by  a  combined  roasting  and  dis- 
tilling process.  The  ore  is  heated  in  furnaces,  the  mercury  is  vaporized 
and  is  then  collected  in  condensers. 

The  roasting  may  be  performed  in  shaft-furnaces  of  the  Scott  type, 
or  in  rotary  furnaces.  The  condensers  are  long  series  of  ])rick  or 
cement  chambers,  or  curved  pipes  cooled  by  water. 

SALT. 

Salt  is  very  abundant  and  widely  distributed  in  the  United  States. 
The  production  is  always  able  to  meet  domestic  requirements,  despite- 
unfavorable  conditions  of  operation  from  time  to  time.  There  is  a 
very  small  export  and  import  trade.  The  largest  part  of  the  pro- 
duction is  obtained  by  converting  the  natural  rock  salt  into  brines,. 


COMMERCIAL   MINERALS  OP   CALIFORNIA.  83 

pumping  this  brine  to  the  surface  and  there  evaporating  it.  Almost 
;;s  great  a  quantity  is  produced  by  evaporating  the  natural  sea  water, 
while  in  1917  about  1,600,000  tons  of  rock  salt  were  mined  in  the 
iiatural  state.     Large  quantities  are  also  obtained  from  natural  brines. 

Michigan  has  for  many  years  been  the  largest  producer,  followed 
closely  by  New  York.  Other  principal  producing  states  in  order  are: 
Ohio,  Kansas,  California,  Louisiana,  Texas  and  Utah. 

Most  of  the  salt  produced  in  California  is  obtained  by  evaporating 
the  ocean  water,  plants  being  located  on  the  coa<st  or  bays  at  San 
Francisco,  Los  Angeles  and  San  Diego.  Formerly  considerable  table 
salt  consumed  in  California  was  obtained  from  eastern  states,  but  for 
the  past  few  years  California  refineries  have  not  only  supplied  our 
own  markets,  but  have  exported  some  to  other  states  and  to  Australia. 

Industrial  application  and  uses. 

Besides  the  well  known  household  uses  of  seasoning  and  preserving 
there  are  other  important  industries  in  w^hich  salt  is  essential,  such 
as  fish  and  meat  packing  and  canning,  dairy  industry,  curing  and 
preserving  hides,  manufacture  of  chemicals,  soap,  glass  and  sodium 
salts,  and  in  bleaching  many  different  materials. 

Properties  and  ores. 

Salt  occurs  in  nature  in  two  distinct  ways — as  rock  salt  in  beds 
associated  with  sedimentary  deposits,  and  in  natural  brines. 

Halite,  Rock  Salt  (NaCl).  Sodium  chloride.  Pure  white,  to 
slightly  reddish  or  yellowish  in  color,  perfect  cubic  cleavage,  vitreous 
luster,  distinctly  salty  taste,  hardness  2.5,  specific  gravity  2.13.  Occurs 
in  large  masses  or  groups  of  cubic  crystals,  or  as  granular  deposits. 

The  sea  water,  which  contains  about  3%  salt,  is  an  inexhaustible 
source  from  which  salt  is  obtained  by  evaporation. 

Distribution. 

In  San  Bernardino  County  there  are  deposits  of  rock  salt  which 
are  worked  by  means  of  quarrying  and  steam  shovels.  There  are  13 
refining  plants  operating  in  Alameda  County,  three  in  San  Mateo, 
two  in  San  Diego  and  one  each  in  Inyo,  Kern,  Los  Angeles,  Mono, 
Monterey,  Solano,  and  San  Bernardino  counties. 

Tests. 

Salt  is  easily  told  by  the  taste  and  appearance.  Also  gives  the 
intense  yellow  color  to  the  flame  due  to  sodium.  The  solution  when 
made  acid  with  nitric  acid  gives  with  silver  nitrate  a  precipitate  of 
silver  chloride. 


64:  CALIFORNIA   STATE    MINING  BUREAU. 

Preparation. 

Salt  is  derived  principally  from  sea  water  by  solar  evaporation. 
Fire  is  seldom  used  for  evaporating,  because  of  the  cost  of  fuel.  The 
water  is  admitted  at  high  tide  into  large  ponds  covering  many  acres, 
and  when  it  has  become  sufficiently  concentrated  by  evaporation,  it 
is  pumped  into  smaller  vats,  which,  in  some  cases,  are  provided  with 
wooden  floors.  The  process  of  evaporation  is  here  continued  to  dry- 
ness, the  salt  covering  the  bottom  of  the  vats  from  six  inches  to  one 
foot  in  depth.     It  is  then  gathered,  hauled  to  the  refinery  and  stacked. 

The  crude  salt  is  washed  in  a  concentrated  solution,  and  then  re- 
dissolved  in  pure  fresh  water.  The  brine  goes  to  settling  tanks,  where 
it  remains  for  about  twenty-four  hours.  After  leaving  the  settling 
tanks,  it  goes  through  a  system  of  sterilization  and  filtration,  which 
removes  all  impurities  and  is  then  evaporated  in  large  pans.  The 
product  is  pure  crystallized  salt.  This  is  dried,  ground,  and  graded 
for  the  various  uses. 

When  the  brines  are  pumped  from  natural  salt  deposits,  they  are 
treated  much  as  above,  but  the  solutions  are  often  of  such  concentration 
to  warrant  evaporation  by  fire. 


SANDSTONE. 

The  production  of  sandstone  has  decreased  greatly  in  the  last  few 
years,  due  to  the  increase  in  the  use  of  reinforced  concrete,  and* 
granite,  in  building  construction. 

There  is  a  great  amount  of  high  grade  sandstone  in  California,  the 
best  known  quarries  being  those  in  Colusa  County.  These  have  been 
closed  during  the  last  few  years  because  of  the  production  elsewhere 
of  a  lighter  colored  material. 

Many  large  buildings  in  San  Francisco  and  other  cities  are  con- 
structed of  Colusa  sandstone,  among  the  most  noteworthy  in  San 
Francisco  being  the  Ferry  Building,  Saint  Francis  Hotel,  Flood  Build- 
ing, Humboldt  Savings  Bank,  Monadnock  Building,  Kohl  Building 
and  Merchants  National  Bank. 

SILICA,  SAND   AND  QUARTZ. 

Silica,  as  here  used,  includes  that  utilized  for  all  purposes  except 
for  concrete,  mortar  and  other  building  purposes,  and  for  gem  stones. 
In  the  glass  and  pottery  industries  there  is  an  enormous  demand  for 
good  quality  silica.  The  greatest  demand  comes  from  the  large  manu- 
facturing centers.  The  most  important  producing  states  are  Maryland, 
California,  Pennsylvania,  Illinois,  Massachusetts,  Michigan,  New  Jer- 
sey and  Tennessee. 


COMMERCIAL   MINERALS   OP   CALIFORNIA.  85 

Industrial  application  and  uses. 

Silica   is  used   principally   in   the   manufacture   of   glass,   pottery, 

aints,  scouring  soaps,  and  abrasive  and  polishing  materials.     Much 

sand  is  used  as  a  building  material  in  concrete,  mortar,  foundry  work, 

etc.,  but  the  material  used  in  this  way  is  not  included  in  the  figures 

given  here. 

Silica  is  the  basis  of  all  glass  manufacture,  and  in  the  pottery 
industry-  it  is  used  in  the  body  of  the  ware  to  reduce  shrinkage,  and 
also  in  the  glazes.  The  pigments  in  some  paints  contain  as  much  as 
one-third  finely  ground  silica.  The  finely  ground  material  is  better 
for  this  purpose  than  the  fine  natural  sand,  because  of  its  angularity 
rnd  better  adhering  qualities.  It  is  also  better  for  soaps,  scouring 
material  and  polishing  powders.  Crushed  quartz  of  various  size  is 
used  in  making  sandpaper,  sand  belts  and  material  for  sand-blast 
apparatus. 

Much  silica  is  used  as  a  flux  in  copper  smelting,  and  other  metal- 
lurgical processes,  assaying,  etc.,  and  in  the  manufacture  of  ferro- 
silicon  and  other  alloys  in  the  electric  furnace. 

Properties. 

Silica  (SiOo)  occurs  in  deposits  of  commercial  importance  in  many 
different  forms,  such  as  sand,  sandstone,  vein  quartz,  quartzite,  flint, 
tripolite,  etc.  In  all  its  various  forms  quartz  makes  up  about  three- 
fifths  of  the  solid  crust  of  the  earth,  and  is  therefore  very  common. 

Quartz  occurs  in  many  varieties  either  crystalline  or  compact  mas- 
sive. Large  masses  of  crj'stals  in  hexagonal  prisms  and  pyramids  are 
frequently  found.  The  color  varies  from  pure  white  to  yellow,  brown, 
red-brown,  amethyst,  rose,  etc.,  vitreous  luster,  hardness  7.0,  specific 
gravity  2.65,  prominent  conchoidal  fracture.  Veins,  ledges,  seams 
and  masses  of  white  quartz  are  common  in  volcanic  and  metaraorphic 
areas  and  much  of  it  is  gold  bearing. 

Sand  is  composed  principally  of  fine  particles  of  quartz,  and  sand- 
stone is  formed  by  the  natural  cementing  of  these  particles. 

Flint  is  a  hard,  dark  amorphous  form  of  silica. 

Distribution. 

Silica  was  produced  commercially  in  1918  from  13  properties  in 
Amador,  El  Dorado,  Monterey,  Placer,  Riverside,  and  Tulare  counties. 

Both  quartz  and  sand  are  so  abundant  that  it  is  only  a  question 
of  locating  deposits  of  sufficient  purity  which  can  be  econojnicallj^ 
marketed. 


86  CALIFORNIA   STATE   MINING  BUREAU. 

Tests. 

Quartz  or  silica  is  so  common  and  well  known  that  it  is  not  difficult 
to  detect.  The  easiest  test,  and  one  which  illustrates  the  principle 
of  ^lass  manufacture  is  made  by  fusing  before  the  blowpipe  a  little 
of  the  powdered  mineral  with  an  equal  volume  of  sodium  carbonate. 
This  may  also  be  done  by  making  the  mixture  into  a  paste  with  water 
and  heating  on  a  loop  of  platinum  wire  or  on  a  piece  of  clean  char- 
coal.    A  clear  glass  bead  should  result. 


SILVER. 

The  principal  producing  silver  states  in  the  order  of  the  value  of 
their  production  in  1916  were:  Montana,  Nevada,  Utah,  Idaho,  Colo- 
rado, Arizona  and  California. 

The  rise  in  the  price  of  silver  in  the  last  few  years  has  been  phenom- 
enal. From  an  average  of  50.7^  per  ounce  in  1915  it  increased  to 
65.8^  in  1916,  82.4^  in  1917,  96.7^  in  1918,  and  111.12  in  1919.  In 
September  1917,  the  price  reached  the  highest  point  in  40  years,  the 
quotations  being  around  $1  per  ounce. 

The  production  of  silver  in  California  comes  principally  from  the 
copper,  lead,  zinc  and  gold  mines.  The  greatest  output  is  from  Inyo 
and  Shasta  counties.  In  Inyo  County  the  production  comes  from  the 
extensive  silver-lead  deposits  of  that  district  and  in  1918  the  silver 
output  from  this  county  Avas  valued  at  $441,548.  In  Shasta  County 
the  silver  is  derived  from  the  large  output  of  copper,  and  in  1918 
the  production  of  silver  was  valued  at  $420,410.  Other  important 
producing  counties  are  Calaveras,  San  Bernardino,  Plumas,  Nevada 
and  Amador. 

Total  production  in  California  in  1918  was  valued  at  $1,427,861. 

SLATE. 

Pennsylvania  is  by  far  the  largest  producer  of  slate,  followed  by 
Vermont,  Virginia,  Maryland,  New  York,  Maine,  New  Jersey,  Tennes- 
see, Utah  and  California. 

The  only  production  in  California  since  1910  was  in  1915  when  1000 
squares  were  produced,  valued  at  $5,000.  Considerable  slate  is  ex- 
ported to  Canada,  South  America,  and  the  West  Indies. 

Industrial  application  and  uses. 

Slate  is  used  for  roofing  material,  architectural  purposes,  various 
structural,  electrical  and  sanitary  purposes,  school  slates  and  black- 
board material.  The  architectural  slate  must  be  of  unusual  thick- 
ness— from  three-sixteenths  of  an  inch  up  to  two  inches.     The  demand 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  87 

for  roofing  slate  has  decreased  in  the  last  few  years,  because  of  many 
patent  roofing  materials  recently  put  on  the  market.  Various  grades 
of  material  for  structural  and  sanitary  purposes  are  known  as  will 
stock.  Other  uses  for  slate  are  for  tombstones,  billiard  table  tops, 
ground  slate  for  roofing  material  and  a  few  minor  uses. 

Properties  and  ores. 

Slate  is  a  fine-grained  metamorphosed  sedimentary  rock,  with  a 
close  crystalline  texture.  The  most  striking  characteristic  and  the  one 
which  gives  it  its  economic  value  is  the  prominent  cleavage.  It  may 
be  split  or  broken  into  very  thin,  smooth  slabs.  It  is  generally  bluish- 
uray,  but  is  often  highly  colored  by  various  oxides.  It  is  soft  enough  to 
be  easily  scratched  with  a  knife,  yet  so  dense  that  it  rings  when  struck 
with  a  hammer. 

In  composition  the  slates  are  composed  of  about  56%  silica  (SiOg), 
249;  aluminum  oxide  (AloOg),  and  varying  amounts  generally  from 
2  to  5%  of  the  oxides  of  magnesium,  calcium,  iron,  potassium  and 
sodium. 

Distribution. 

Slat'^  was  first  produced  in  California  in  1889,  and  the  production 
was  '-ontinuous  up  to  and  including  1910.  This  production  came  from 
large  deposits  in  El  Dorado,  Calaveras,  and  Mariposa  counties.  The 
property  of  the  Sierra  Slate  Corporation,  fo-rmerly  the  Eureka  Slate 
Company,  in  El  Dorado  County  was  operated  on  an  extensive  scale. 
The  product  is  of  such  good  quality  that  it  has  been  accepted  by  the 
government  as  suitable  for  federal  work. 

Tests. 

The  physical  properties,  especially  the  prominent  easy  cleavage,  are 
the  determining  factor  in  securing  a  body  of  commercial  value.  It  also 
must  bo  fine-grained,  and  the  cleavage  plates  must  be  of  considerable 

size. 

SODA. 

The  war  has  greatl}-  stimulated  the  soda  industry  in  the  United 
States,  because  of  discontinued  imports,  and  in  order  to  supply  foreign 
countries  where  production  has  been  cut  down.  Sodium  products  have 
replaced  those  of  potassium  in  many  industries. 

Industrial  application  and   uses. 

The  principal  uses  for  the  soda  materials  are  in  the  manufacture 
of  glass,  soap  and  paper,  in  sugar  refining,  in  the  preparation  of 
caustic  soda  or  sodium  hydroxide   (NaOH),  and  recently  to  some  ex- 


88  CALIFORNIA   STATE   MINING  BUREAU. 

tent  in  tanning,  match  making  and  the  manufacture  of  cyanide  for 
extracting  gold  and  silver  from  their  ores. 

Properties  and  ores. 

Sodium  is  a  silver  white  metal,  so  soft  that  it  may  be  easily  cut 
with  a  knife  or  moulded  with  the  fingers.  It  floats  upon  water  (spe- 
cific gravity  0.98)  and  decomposes  it  at  ordinary  temperature,  liberating 
hydrogen.  It  burns  at  low  temperature  with  a  brilliant  yellow  flame, 
tarnishes  easily  in  moist  air,  the  surface  becoming  covered  with  a 
brownish  coating. 

Sodium  carbonate  (NasCOg)  is  prepared  by  two  well-known  pro- 
cesses: the  Leblanc  and  the  Solvay.  In  the  Leblanc  process  sodium 
chloride  or  common  salt  is  first  changed  into  sodium  sulphate  by 
sulphuric  acid. 

2  NaCl  +  H.SO,  =  HNaSO,  +  HCl  +  NaCl 
HNaSO,  +  NaCl  =  Na^SO^  +  HCl 

The  impure  product  (Na2S04)  is  called  'salt  cake,'  and  hydro- 
chloric acid  is  a  by-product.  The  salt  cake  is  changed  into  sodium 
carbonate  by  heating  with  coal  and  limestone. 

Na2S04  +  2C  =  Na^S  +  200^ 

Na^S  +  CaCOg  =  Na^COg  -f  CaS 

The  sodium  carbonate  is  separated  from  the  impure  product  by 
dissolving  in  water.  After  evaporation  and  ignition  the  product  is 
*soda  ash,'  and  from  this  is  produced  'sal  soda'  or  'washing  soda' 
(NasCOg.lOH^O). 

In  the  Solvay  process  a  cold  concentrated  solution  of  salt  is  satu- 
rated, first  with  ammonia  gas  and  then  with  carbon  dioxide  gas. 

Sodium  bicarbonate  (HNaCOg)  is  a  by-product  qf  the  Solvay 
process.  It  is  a  white  powder,  less  soluble  in  water  than  the  normal 
carbonate,  and  when  heated  or  mixed  with  an  acid  or  an  acid  salt,  gives 
up  its  carbon  dioxide.  This  led  to  its  use  as  'cooking  or  baking  soda.' 
Baking  powder  is  a  mixture  of  soda  and  cream  of  tartar. 

Trona  (Na2CO3.HNACO3.2HoO)  Natural  hydrous  bicarbonate  of 
sodium.  Found  only  in  dry  protected  places  as  crystals  and  finely 
fibrous  coatings.  Color  white,  vitreous  luster,  alkaline  taste,  hard- 
ness 2.5-3.0,  specific  gravity  2.1. 

Natron  (NagCOg.lOHgO)  Hydrous  carbonate  of  sodium.  Color 
white,  vitreous  luster,  hardness  1.0-1.5,  specific  gravity  1.42-1.46, 
alkaline  taste.     Occurs  mixed  with  trona. 

Thenardite  (Na2S04)  Sodium  sulphate.  Color  white,  vitreous  lus- 
ter, hardness  2.68-3.0,  specific  gravity  2.68-2.69. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  89 

Glauhente  (Na2S04.CaS04)  Sulphate  of  sodium  and  calcium. 
Color  white,  gray  or  yellor,  vitreous  luster,  hardness  2.5-3.0,  specific 
gravit}"  2.7-2.85,  perfect  basal  cleavage. 

Hanksite  (4Na2S04.Na2C03)  Double  soda  salt.  Color  white,  vitre- 
ous luster,  hardness  3.0-3.5,  specific  gravity  2.56,  saline  taste. 

Distribution. 

The  commercial  production  of  soda  ash  and  sodium  bicarbonate  in 
California  in  1918  came  from  three  plants  located  at  Owens  Lake  in 
Inyo  County,  and  comprised  about  93%  of  the  total  value  of  soda 
products  marketed. 

Natural  sulphate  came  from  the  Carrizo  Plains,  San  Luis  Obispo 
County,  a  natural  carbonate  from  Dorris,  Siskiyou  County,  and  sul- 
phate from  the  natural  brines  of  Searles  Lake,  San  Bernardino  County. 

Tests. 

All  sodium  minerals  give  the  characteristic  .vellow  flame  test.  The 
carbonates  natron  and  trona  effervesce  when  treated  with  acids,  and 
their  aqueous  solutions  give  an  alkaline  reaction  with  turmeric  paper 
i.  e.,  turn  it  reddish-brown.  Natron  dissolves  in  its  water  of  crystal- 
lization when  gently  heated  in  the  closed  tube  and  trona  gives  water 
and  carbon  dioxide  when  similarly  treated. 


MISCELLANEOUS  STONE. 

Under  the  heading  of  miscellaneous  stone  are  included  crushed 
rock  of  all  kinds  for  macadam,  ballast,  rubble,  etc.,  stone  paving  blocks, 
sand,  gravel  and  pebbles  for  grinding  mills.  Thus  grouped  together, 
these  materials  form  one  of  the  most  important  industries  of  the  state, 
amounting  in  19-16  to  a  value  of  $4,171,519  and  in  1917  to  $3,634,767. 
In  both  years  they  ranked  sixth  in  value  of  California  mineral  products. 

Paving  blocks  have  decreased  in  use,  owing  to  the  need  for  smoother 
roadbeds  for  motor  vehicle  traffic.  It  is  difficult  to  make  estimates 
of  this  material,  because  no  definite  record  is  kept  of  a  great  deal  of 
rock  which  is  used  by  almost  every  county  in  building  and  repairing 
roads. 

Grinding-mill  pebbles  were  produced  for  the  first  time  in  California 
in  1915.  These  come  from  the  gold  dredger  tailings  in  Sacramento 
County,  from  beaches  in  San  Diego  County,  and  from  river  gravels 
in  Fresno  County. 

Industrial  application  and  uses. 

Crushed  rock  of  various  sizes  is  used  in  almost  all  concrete  and 
reinforced  concrete  construction,  in  macadam  and  oil  macadam  for 


90  CAT.IFORNIA    STATE    MINING   BUREAU. 

roadways,  and  for  ballast  ou  railways.  Sand  and  gravel  are  also  used 
to  a  great  extent  in  this  class  of  work.  Sand  is  used  in  mortars  and 
cements.  Grinding  pebbles  are  used  in  mills  of  various  kinds  for 
grinding  and  pulverizing  ore  in  mining  operations. 

Properties. 

The  hardest  rocks  such  as  basalt,  diabase,  flint  or  felsite  are  required 
for  grinding-mill  pebbles,  and  these  must  be  well  rounded  and  smooth. 
Paving  blocks  produced  are  basalt,  andesite,  granite,  and  trachyte. 
Rock  crushed  for  concrete  may  be  any  of  these  varieties  depending 
on  the  locality. 

Distribution.  * 

Los  Angeles  County  leads  all  others  in  the  value  of  output  of  mis- 
cellaneous stone,  followed  in  order  by  Alameda,  Contra  Costa,  Sac- 
ramento, Marin,  Sonoma,  and  Fresno.  Nearly  every  county  in  the 
state  produces  this  material  to  some  extent. 


STRONTIUM. 

Until  the  last  two  or  three  years  the  domestic  strontium  deposits 
had  remained  undeveloped  and  search  for  new  deposits  had  not  been 
made.  This  was  due  to  the  fact  that  foreign  ore  from  England,  Prus- 
sia and  Sicily  could  be  obtained  at  a  lower  cost  than  home  ore  could  bo 
produced  and  marketed.  The  known  deposits  of  commercial  import- 
ance are  in  the  South  and  West,  and  prior  to  1916  the  chemical  plants 
manufacturing  strontium  salts  were  on  or  near  the  North  Atlantic 
seaboard.  Freight  rates  therefore  were  the  determining  factor.  Many 
other  difficulties  attached  to  the  commercial  exploitation,  such  as  limited 
market,  small  value,  etc.,  tended  to  keep  the  productio"n  down  to  prac- 
tically "a  negligible  quantity.  However,  with  the  advent  of  the  war 
which  brought  not  only  an  increased  demand  but  a  discontinuance  of 
the  imports,  an  impetus  was  given  to  domestic  production. 

Industrial  application  and  uses. 

Strontium  nitrate  is  used  in  the  manufacture  of  fire  works  and 
signal  rockets  of  all  kinds  on  account  of  the  brilliant  crimson  color 
it  produces.  The  demand  for  it  in  this  industry  has  greatly  increased 
with  the  war.  The  hydroxide  is  used  in  the  sugar  refining  industry. 
Before  the  war  Germany  used  about  100,000  tons  of  strontium 
hydroxide  annually  in  the  beet  sugar  industry  alone.  Great  develop- 
ments can  reasonably  be  expected  along  this  line  in  this  country. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  91 

Properties  and  ores. 

Strontium  is  an  uncommon  metallic  element.  It  never  occurs  free, 
but  forms  many  compounds  that  are  quite  rare  in  nature.  The  sul- 
phate 'celestite'  and  the  carbonate  '  strontianite '  are  the  only  com- 
mercial ores. 

Celestite  (SrSOJ  Strontium  sulphate.  Contains  56.4%  (SrO) 
and  43.6%  (SO3).  Color  white  to  pale  blue,  sometimes  reddish,  vit- 
reous or  pearly  luster,  nearly  perfect  cleavage  in  Hiree  directions  at 
right  angles  to  one  another.  It  is  heavy  (specific  gravity  3.0)  and 
soft  enough  to  be  scratched  with  a  knife  (hardness  3.0-3.5).  Resembles 
barite  (BaSO^).  Occurs  as  a  massive,  finely  crystalline  rock  which 
closely  resembles  crystalline  limestone,  or  in  long,  slender  tabular  or 
fibrous  crA'stals. 

Strontianite  (SrCO^)  Strontium  carbonate.  Contains  70.3%  (SrO) 
and  29.7%  (CO2).  Color  white,  pale  green  or  yellow,  vitreous  or 
resinous  luster,  heavy  (specific  gravity  3.7)  and  easily  scratched  by  a 
knife  (hardness  3.5-4.0).  It  may  be  either  transparent  or  translucent, 
is  quite  brittle  and  has  prismatic  cleavage.  Usually  found  in  needle- 
shaped  crystals.  It  is  the  most  valuable  ore  of  strontium,  but  is  rarely 
found  in  bodies  of  commercial  size. 

Distribution. 

The  production  in  California  has  been  from  celestite  deposits  in 
Imperial  County  and  from  strontianite  deposits  near  Barstow  in  San 
Bernardino  County.  Celestite  'also  occurs  in  the  Avawatz  Mountains 
in  San  Bernardino  County  and  in  Inyo  County.  Besides  California, 
there  has  been  production  of  the  sulphate  in  Arizona,  Washington, 
New  York,  Texas,  Ohio,  Utah  and  Michigan. 

Strontium  ores  are  found  in  beds  of  sandstone,  limestone,  gypsimi, 
rock  salt  and  clay.  They  are  closely  associated  with  the  sediments 
formed  by  the  drying  up  of  the  lakes  of  the  Tertiary  period. 

Tests. 

The  principal  tests  for  strontium  are  the  crimson  flame  test  and 
the  alkaline  reaction  after  heating.  For  the  color  test  a  hot,  non- 
luminous  (blue)  flame,  such  as  given  by  an  alcohol  lamp  or  a  blow- 
pipe i-s  required.  The  mineral  is  pulverized  and  heated  with  hydro- 
chloric acid.  The  solution  is  evaporated  until  it  is  fairly  thick.  A 
loop  of  clean  platinum  wire  is  dipped  into  the  concentrated  solution 
and  heated  in  the  blue  flame.  If  strontium  is  present  a  brilliant 
crimson  color  will  appear,  which  must  be  distinguished  from  the  yellow 
color  oiven  by  sodium  and  barium.  Both  the  sulphate  and  the  car- 
l)()iiatc    when   heated   before   the   blowpipe   and   placed   on   moistened 


92  CALIFORNIA   STATE   MINING  BUREAU. 

turmeric  paper,  will  turn  it  red  (alkaline  reaction).  The  carbonate 
when  "heated  before  the  blowpipe,  swells  and  spouts,  while  the  sulphate 
flies  to  pieces  (decrepitates),  but  the  latter  will  fuse  at  low  tempera- 
tures. 

Preparation. 

Strontium  nitrate  is  prepared  by  treating  the  natural  carbonate, 
strontianite,  with  .hot  nitric  acid  (HNO3). 

The  hydroxide,  Sr(0H)2  may  be  prepared  in  a  great  number  of 
ways  from  either  celestite  or  strontianite.  In  one  process,  strontianite 
is  treated  with  superheated  steam,  while  another  method  is  to  roast 
celestite  with  coal  and  brown  iron  ore. 

Metallic  strontium  is  best  obtained  by  electrolysis  of  the  fused 
chloride. 


SULPHUR. 

There  is  a  great  demand  for  sulphur  in  the  manufacture  of  sul- 
phuric acid,  both  for  agricultural  and  war  munition  purposes.  It  is 
estimated  that  463,36-i  long  tons  were  used  for  this  purpose  alone  in 
1917.  This  was  more  than  100,000  tons  greater  than  the  entire  domes- 
tic consumption  for  all  purposes  in  1914,  notwithstanding  the  fact  that 
under  ordinary  conditions  about  150,000  tons  are  used  annually  in 
the  manufacture  of  paper.  In  1914  the  total  production  in  the  United 
States  was  327,634  long  tons,  and  the  imports  for  the  some  year  were 
26,135  long  tons.  In  the  last  three  years  99%  of  the  domestic  produc- 
tion came  from  two  companies  and  for  this  reason  no  figures  are  pub- 
lished. However,  in  1917  the  production  had  increased  sufficiently 
to  supply  all  demands  and  leave  152,821  loDg  tons  for  export.  The 
imports  were  less  than  1000  tons. 

There  has  been  no  commercial  production  in  California  since  1865- 
1868,  in  which  period  a  total  of  941  tons  valued  at  $53,500  was  shipped 
from  the  famous  Sulphur  Bank  Mine  in  Lake  County. 

Industrial  application  and  uses. 

Under  normal  conditions  the  greatest  amount  of  sulphur  is  used 
in  the  manufacture  of  paper  and  the  preparation  of  cliemicaLs.  One- 
eighth  of  a  ton  is  used  for  each  ton  of  sulphite  pulp  manufactured. 
In  the  last  few  years  however,  greater  quantities  have  been  used  in  the 
manufacture  of  sulphuric  acid.  Never  before  has  so  much  sulphuric 
acid  been  used  in  this  country.  This  is  due  to  its  application  in  so 
many  industries,  many  of  which  had  a  direct  bearing  upon  the  war 
plan.     Notable   among  these   are:   the   manufacture   of   almost   every 


COMMERCIAL    MINERALS   OP   CALIFORNIA.  93 

other  kind  of  acid,   purification  and  refining  of  many  oils,  making 
sulphate  of  soda    (salt  cake),  soap,  glass,  fertilizers,  etc. 

Considerable  quantities  of  native  sulphur  are  also  used  in  the  manu- 
facture of  explosives,  fireworks  and  matches  and  for  medicinal  pur- 
poses and  as  a  germicide. 

Properties  and  ores. 

Native  sulphur  (S)  is  yellow  in  color,  brittle,  resinous  luster,  soft 
(hardness  1.5-.5)  and  light  (specific  gravity  2.0).  Has  a  conchoidal 
or  uneven  fracture.  Burns  with  a  blue  flame  and  gives  off  strong 
odor  of  sulphur  dioxide.  Occurs  in  beautiful  crystals  or  in  massive 
stalactitic  and  spherodial  forms.  Often  impure  through  the  presence 
of  clay  and  bituminous  matter. 

Distribution. 

Sulphur  both  free  and  combined  is  abundant  and  widely  distributed. 
Native  sulphur  is  found  usually  in  regions  of  volcanic  activity,  geysers, 
hot  springs,  etc.,  where  it  is  formed  through  the  oxidation  of  hydrogen 
sulphide  (HgS).  There  are  also  beds  associated  with  gypsum,  which 
were  no  doubt  formed  by  the  reduction  of  the  gypsum  (CaSO^)  with 
limestone  and  sulphur. 

Two  companies:  the  Union  Sulphur  Company  in  Louisiana  and  the 
Freeport  Sulphur  Company  in  Texas,  furnished  99%  of  all  the  sulphur 
produced  in  the  United  States  in  1917.  Small  amounts  have  been  pro- 
duced in  Nevada,  Utah,  Idaho,  Wyoming  and  Alaska. 

There  is  at  present  no  commercial  output  of  this  mineral  in  Cali- 
fornia, although  it  has  been  found  to  some  extent  in  many  counties, 
namely :  Colusa,  Imperial,  Inyo,  Kern,  Lake,  Mariposa,  San  Bernardino 
and  Sonoma.  During  the  years  1865-1868  sulphur  was  produced  at 
the  Sulphur  Bank  mine  in  Lake  County.  Later,  the  mine  became 
valuable  for  its  quicksilver. 

Tests. 

When  once  seen  the  mineral  is  readily  recognized  by  its  physical 
properties.  An  easy  and  distinguishing  test  is  its  ready  inflammability, 
burning  with  a  faint  blue  flame  and  giving  off  an  irritating  odor.  It 
will  not  dissolve  in  water,  but  is  soluble  in  carbon  disulphide.  It  is  a 
non-conductor  of  heat,  and  the  warmth  of  the  hand  sometimes  causes 
it  to  crackle  or  break. 

Preparation. 

In  Louisiana  and  Texas  the  crude  sulphur  is  mined  by  melting  with 
superheated  steam  and  then  pumping  the  liquid  to  the  surface,  where 
it  cools  and  Sgain  becomes  solid. 


94  CALIFORNIA   STATE    MINING  BUREAU. 

This  method  yields  an  excellent  quality  of  sulphur  without  the 
formation  of  sulphur  dioxide.  The  largest  part  of  the  world's  suppl.y 
of  sulphur  now  comes  from  these  two  states. 

At  the  refineries,  the  raw  material  from  the  mines  is  treated  by  a 
process  of  sublimation,  condensation,  grinding  and  classification 
through  various  sizes  of  screens  for  the  production  of  the  many  grades 
of  pure  sulphur. 

Treatment  with  a  solution  Avhich  boils  above  the  melting  point  of 
sulphur  has  proven  successful  for  many  ores.  A  solution  of  calcium 
chloride  is  used  and  the  ore  suspended  in  an  iron  crate  in  this  boiling 
solution.  The  sulphur  melts,  drops  to  the  bottom  of  the  tank,  and 
is  drawn  off,  while  the  impurities  remain  in  the  crate,  a  fairly  pure 
product  is  obtained  with  no  loss. 

TALC-SOAPSTONE. 

The  United  States  produces  and  uses  more  talc  than  any  other 
coiintry  in  the  world.  The  producing  states  are  California,  Georgia, 
Maryland,  Massachusetts,  New  Jersey,  New  York,  North  Carolina, 
Pennsylvania,  Vermont  and  Virginia.  New  York  and  Vermont  are 
the  largest. producers. 

The  imports  for  1917  were  less  than  one-tenth  of  the  domestic  pro- 
duction, but  a  large  percentage  of  that  which  was  imported  was  of 
very  high  grade.     More  than  half  of  the  imports  come  from  Canada. 

The  price  in  1917  ranged  from  $3  to  $8  per  ton  for  the  lowest  grade 
material,  the  rough  or  crude  talc,  while  the  highest  grade,  which  is 
used  for  insulators,  gas  tips,  etc.,  brought  from  $50  to  $200  per  ton. 
The  value  of  the  crude  is  greatly  increased  by  grinding,  in  which 
state  it  is  worth  from  $5  to  $20  per  ton. 

Industrial  application  and  uses. 

In  its  natural  state  talc  appears  as  the  so-called  French  chalk  and  in 
crayons  used  by  tailors.  In  ground  form  it  is  most  commonly  seen 
as  toilet  powders,  lubricating  mixtures,  etc.,  although  its  most  exten- 
sive use  is  as  a  filler  in  the  manufacture  of  paper.  Much  is  used  for 
insulators,  gas  tips,  etc.,  and  in  the  manufacture  of  rubber  and  cer- 
tain kinds  of  paints. 

Soapstone  is  used  in  the  manufacture  of  laboratory  table  tops,  laun- 
dry   tubs,    tanks,    sinks,    fume    hoods,    switchboards    and    in    general^ 
insulation. 

Properties  and  ores. 

Talc  and  soapstone  are  generally  regarded  as  synonymous.  How 
ever,  talc  is  a  mineral,  while  soapstone  is  a  massive  rock  composed 
almost  entirely  of  talc. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  95 

The  mineral  talc  is  a  hydrous  silicate  of  magnesium  (H2Mg3Si40io), 
remarkable  for  its  softness,  greasy  luster  and  feel  and  its  heat-resisting 
qualities.  It  is  one  of  the  softest  minerals,  being  taken  as  number 
one  in  the  scale  of  hardness.  In  color  it  may  be  white,  gray,  pale 
green  or  brown.  Quite  light  (specific  gravity  2.7-2.9).  Insoluble  in 
ordinary  acids,  difficultly  fusible  and  has  low  electric  conductivity. 
Occurs  in  compact,  foliated  masses  in  metamorphic  areas  and  as  talc 
schists  and  gouge  in  mines.  Generally  a  hydration  product  in  the 
alteration  of  magnesian  silicates  and  is  often  associated  with  serpen- 
tine and  actinolite. 

Distribution. 

Talc  and  soapstone  occur  widely  distributed  throughout  California, 
but  only  a  few  deposits  have  proven  of  commercial  value.  High  grade 
deposits  have  been  developed  in  Inyo  and  San  Bernardino  counties, 
and  considerable  production  has  been  made  in  Amador,  El  Dorado  and 
Tulare  counties.  Occurrences  have  been  noted  in  almost  every  county 
in  the  state. 

Tests. 

Distinguished  by  its  softness,  greasy,  pearly  luster  and  greasy  feel. 
Not  acted  upon  by  hydrochloric  or  sulphuric  acid.  Gives  a  little  water 
upon  intense  ignition  in  the  closed  tube.     Very  difficultly  fusible. 

The  massive  soapstone  variety  is  generally  schistose  and  grayish 
green  in  color,  and  has  a  very  greasy  feel. 

Preparation. 

Soapstone  is  cut  into  slabs  for  the  purposes  mentioned  above,  while 
the  mineral  talc,  or  exceptionally  pure  soapstone,  is  ground  for  powder, 
and  other  uses. 


TIN. 

Along  with  the  other  metals,  but  probably  to  less  extent,  the  use  for 
tin  has  increased  with  the  war  industries.  It  is  one  of  the  oldest 
known  metals,  and  was  obtained  from  the  British  Isles  long  before  the 
Christian  era.  Many  of  the  most  ancient  bronzes  contain  tin.  The 
Cornwall  mines  in  England  were  famous  for  a  long  period,  but  are 
now  practically  exhausted.  More  than  one-half  of  the  world's  pro- 
duction is  obtained  from  placers,  mainly  in  the  Malay  Peninsula,  the 
islands  of  Banca  and  Billiton  near  Sumatra,  and  Australia.  The 
United  States  is  the  largest  consumer  of  tin  among  the  nations,  and 
is  supplied  mostly  by  imports.     In  1917  there  were  71,845  short  tons 


96  CALIFORNIA   STATE    MINING  BUREAU. 

of  tin  imported,  and  the  t(ital  domestic  production  was  only  90  short 
tons.  Besides  the  countries  mentioned  above,  imports  were  received 
from  England,  Bolivia  and  China. 

In  California  tin  has  not  been  produced  commercially  since  1891 
and  1892.  During  these  two  years  about  251,000  pounds  valued  at 
$60,000  were  produced  from  a  small  deposit  near  Corona  in  Riverside 
County. 

Industrial  application  and  uses. 

Tin  is  used  in  making  tin  plate,  tin  foil,  and  various  alloys  such 
as  solder,  bearing  metals,  electrotype  metal  and  bronze.  Solder  is 
one-third  tin  and  two-thirds  lead.  Tin  amalgam  is  used  to  coat  mir- 
rors. Ordinary  tin-ware  is  sheet  iron,  coated  by  dipping  it  into  molten 
tin,  and  hooks,  nails,  etc.,  are  similarly  treated.  Pins  are  made  of 
brass,  and  coated  with  tin. 

Chlorides  of  tin  are  used  in  the  silk  industry  and  in  dyeing  and 
printing  cloth,  such  as  calico.     The  oxides  are  used  for  enameling. 

Properties  and  ores. 

Native  tin    (Sn)    is  a  pure  white  metal,  with  metallic  luster,  soft  • 
(hardness  2.0),  malleable  and  quite  heavy  (specific  gravity  7.2).    Does 
not  tarnish  readily  in  the  air.     Occurs  in  rounded  grains. 

There  are  two  principal  ores,  a  sulphide  and  an  oxide. 

Cassiterite  (SnOa)  Tin  oxide.  Tin  stone.  This  is  the  principal 
ore  of  tin,  from  which  practically  all  of  the  metal  is  obtained.  It  is 
rare  in  California.  Contains  78.7%  Sn.  and  21.3%  O.  Color  black, 
brown  or  yellow,  streak  pale  brown  to  gray,  adamantine  luster,  hard- 
ness 6.7,  gravity  6.4  to  7.0.  Occurs  massive,  in  grains,  square  prisms, 
octohedrons  or  twins.  Cleavage  indistinct.  Resem^bles  dark  garnet 
or  tourmaline.  Found  in  veins  in  granite,  gneiss  and  mica  schist, 
fxssociated  with  pyrite,  topaz,  tourmaline,  talc  and  mica. 

Stannite  (SnSgCugS.FeS)  Tin  sulphide.  Tin  pyrites.  Contains 
27%  tin,  3%  copper,  30%  sulphur  and  13%  iron.  Steel  gray  to  iron 
black  in  color,  black  streak,  brittle,  hardness  4.0,  gravity  4.3-4.6. 
Occurs  commonly  massive  or  in  grains. 

Distribution. 

Small  amounts  of  stream  tin  are  recovered  in  Alaska  in  connection 
with  gold  dredging.  It  has  also  been  produced  to  some  extent  in  the 
Black  Hills  in  South  Dakota  and  in  North  and  South  Carolina. 

In  California  it  has  been  found  in  Riverside,  San  Diego,  Fresno, 
Plumas,  Siskiyou  and  Trinity  counties. 


COMMERCIAL   MINERALS  OF   CALIFORNIA.  97 

Tests. 

To  test  cassiterite,  the  powdered  mineral  when  heated  before  the 
blowpipe  on  charcoal  with  sodium  carbonate  and  charcoal  powder 
gives  globules  of  metallic  tin.  The  fused  mass  may  have  to  be  crushed 
and  washed  to  show  the  metallic  globules.  If  a  fragment  of  the  min- 
eral is  treated  with  dilute  hydrochloric  or  sulphuric  acid  and  granu- 
lated zinc,  hydrogen  is  generated  and  the  fragment  of  mineral  is 
coated  with  tin,  which  has  a  dull  gray  appearance.  This  becomes 
bright  when  rubbed  with  the  hand  and  gives  off  a  characteristic  odor. 

Stannite  when  fused  alone  on  charcoal  gives  a  white  coating  of  tin 
oxide.     After  heating  it  is  slightly  magnetic. 

Metallurgy. 

The  oxide  cassiterite,  is  reduced  with  coal  or  charcoal  in  either  a 
blast  or  reverberatory  furnace. 


TUNGSTEN. 

The  increase  in  the  production  of  tungsten  in  California  has  been 
phenomenal.  In  1914  the  tungsten  produced  was  valued  at  $180,575. 
In  1916  this  had  increased  to  a  production  valued  at  $4,571,521.  Pre- 
vious to  1915  a  single  company  produced  almost  all  of  California's 
tungsten.  Because  of  the  high  prices  prevailing  in  the  latter  part  of 
1915  and  in  1916,  prospecting  was  greatly  stimulated  and'  the  tungsten- 
bearing  areas  in  the  southern  part  of  the  state  in  Kern  and  San 
Bernardino  counties  were  considerably  extended.  Deposits  were  also 
found  and  opened  up  in  Inyo  County. 

The  above  recent  production  in  California  is  more  noticeable,  in 
view  of  the  fact  that  before  1900  the  total  production  in  the  United 
States  was  insignificant,  because  of  imports  from  China  and  Bolivia, 
which  are  low-paid  labor  countries. 

Tlie  value  of  tungsten  ore  is  generally  based  upon  the  content  of 
tungsten  trioxide  (WO3),  and  quotations  are  made  per  unit,  the  unit 
being  1%  of  WO3  in  a  ton.  In  the  early  part  of  1914  prices  were  low, 
being  $6.50  per  unit.  Such  a  price  offered  slight  inducement  to  the 
miner  or  prospector,  and  as  a  consequence,  the  production  was  lower 
even,  than  in  previous  years.  Toward  the  end  of  the  year,  due  to 
the  war,  the  price  raised  to  $9  per  unit,  and  the  demand  for  the  ore 
was  greatly  increased.  In  1916  the  price  roi^  to  $36  per  unit  for 
60%  WOJ. 

Industrial  application  and  uses. 

Tungsten  is  used  in  the  greatest  amounts  as  an  alloy  with  steel. 
It  produces  a  hard,  tough  variety  which  is  capable  of  holding  its 

7—2484 


98  CALIFORNIA   STATE    MINING  BUREAU. 

temper  up  to  nearly  a  red  heat.  It  is  used  either  alone  or  with 
molybdenum  or  chromium,  in  such  steels.  The  product  is  made  into 
armor  plates,  projectiles,  steel  tools,  etc.  It  is  used  in  the  manufacture 
of  filaments  for  electric  light  bulbs.  Although  millions  of  bulbs  are 
made  every  year,  the  amount  of  tungsten  used  in  this  way  is  very 
small,  owing  to  the  fineness  of  the  filaments.  It  is  used  in  place  of 
platinum  for  crucibles  and  electric  furnaces,  and  for  chemical  appara- 
tus, on  account  of  great  resistance  to  acids.  Minor  uses  are  for  spark 
plugs,  phonograph  needles,  etc. 

Properties  and  ores. 

Tungsten  (W)  is  a  hard,  heavy,  tough  metal.  Hardness  4.5  to  8.0. 
Specific  gravity  19.3-20.2.  It  has  a  high  melting  point  and  for  this 
reason  is  obtained  from  its  ores  in  the  form  of  a  powder.  It  is  very 
resistant  to  the  action  of  the  atmosphere  and  ordinary  acids.  It  forms 
alloys  readily  with  other  metals. 

The  principal  ores  of  tungsten  are  scheelite,  wolframite,  hiibnerite, 
and  ferberite. 

Scheelite  (CaW04).  Calcium  tungstate.  White,  yellow,  green  or 
brown  mineral,  with  a  vitreous  or  adamantine  luster.  Transparent  or 
translucent.  Hardness  4.5  to  5.0.  Gravity  6.0.  Occurs  massive  or  in 
pyramidal  crystals.  It  is  the  principal  ore  of  tungsten  in  California, 
and  is  produced  in  the  largest  quantities. 

Huhnerite,  wolframite  and  ferberite  are  similar,  being  tungstates 
of  iron  and  manganese.  The  first-named  is  essentially  a  manganese 
tungstate,  with  a  minimum  of  iron.  The  last-named  is  essentially 
iron  tungstate,  with  a  minimum  of  manganese;  and  wolframite  con- 
tains iron  and  manganese  in  about  equal  proportions.  No  ferberite 
has  thus  far  been  found  in  California.  Wolframite — hiibnerite ;  color, 
brownish  black  to  brownish  red;  streak  dark  brown  to  black.  Luster 
metallic  to  submetallic;  hardness  5.0-5.5;  gravity  7.2-7.5.  Occurs 
massive  or  in  thick  tabular  crystals. 

Distribution. 

In  the  Atolia  District  in  western  San  Bernardino  County,  scheelite 
veins  occur  in  granite.  Quartz  and  calcite  accompany  the  scheelite 
as  vein  minerals.  In  the  adjoining  Stringer  or  Kandsburg  District  in 
eastern  Kern  County,  the  veins  are  narrow  stringers  or  seams  of  i 
scheelite  in  schist,  and  are  closely  associated  with  gold  bearing  quartz 
veins,  although,  for  the  most  part,  gold  and  tungsten  are  not  found 
in  the  same  vein.  In  both  the  Bishop  and  Ubehebe  Districts  in  Inyo 
County  the  ores  occur  along  or  near  the  contact  of  granite  and  lime- 
stone. In  the  latter  district  the  ores  are  scheelite  and  hiibnerite,  while 
in  the  former  district  small  crj^stals  of  scheelite  are  associated  with  rose 


COMMERCIAL   MINERALS  OF   CALIFORNIA.  99 

quartz,  garnet,  pyrite,  magnetite  and  other  minerals,  in  the  Signal 
District  in  San  Bernardino  County  the  ore,  mostly  wolframite,  occurs 
in  quartz  veins  in  granite  or  along  the  contact  of  granite  and  limestone. 
There  are  other  known  deposits  in  Fresno,  Madera  and  Nevada  counties. 

Tests. 

The  mineral  is  finely  pulverized  and  heated  with  hydrochloric  acid 
(HCl).  If  tungsten  is  present,  a  yellow  powder,  tungsten  trioxide 
(WO3)  will  be  produced.  Upon  the  addition  of  metallic  zinc  (tin  or 
lead)  the  solution  will  turn  indigo  blue,  the  intensity  of  the  color 
depending  upon  the  amount  of  tungsten  in  the  specimen  tested.  If 
tlie  mineral  is  insoluble,  as  wolframite,  fuse  with  sodium  carbonate, 
and  then  dissolve  in  HCl  and  test  as  above.  Wolframite  and  hiibne- 
rite  may  also  be  tested  for  manganese.  They  give  to  the  borax  bead 
a  violet  color. 

Metallurgy. 

The  ore  is  ground  fine  and  roasted  in  a  reverberatory  furnace  with 
sodium  carbonate,  in  the  form  of  soda  ash,  and  a  small  amount  of 
sodium  nitrate.  The  product  is  leached  in  hot  water,  and  the  insoluble 
tungstate  decomposed  by  hydrochloric  acid.  The  resulting  tungstic 
trioxide  (WO3)  is  reduced  by  charcoal,  in  graphite  crucible.s  in  gas, 
coke  or  electric  furnaces. 

Ferro-tungsten,  containing  from  50%  to  80%  tungsten,  is  made 
by  smelting  concentrate  in  an  electric  furnace.  Coke  is  the  common 
reducing  agent  and  lime  and  silica  are  added  to  form  a  suitable  slag. 
Fluorspar  is  used  to  aid  liquefaction.  Hematite  is  used  as  a  decar- 
l)onizer. 


VANADIUM. 

There  has  been  no  production  of  vanadium  in  California  up  to  the 
present  time.     The  richest  known  deposits  are  located  in  Peru. 

Industrial  application  and  uses. 

Vanadium  is  used  in  the  manufacture  of  very  high  grade  steel, 
from  which  are  made  various  parts  for  automobiles,  aeroplanes,  loco- 
motives, etc.,  and  also,  armor  plate,  war  munitions  and  high-speed 
steel  cutting  tools.  It  is  to  a  large  extent  replacing  nickel  in  this 
regard. 

Dental  and  surgical  instruments,  razors,  etc.,  in  fact  all  tools  re- 
quiring a  keen  cutting  edge  of  toughness  and  lasting  qualities  are 
made  from  vanadium  steel.     Smaller  quantities  are  used  in  the  form 


100  CALIFORNIA  STATE   MINING  BUREAU. 

of  vanadium  salts,  in  dyeing  and  printing  cloth,  and  in  the  manufac- 
ture of  ink,  glass  and  porcelain.  Recently  it  has  come  into  use  in  the 
manufacture  of  a  tough,  dense  rubber,  which  is  absolutely  oil  and 
water  proof. 

Properties  and  ores.  ' 

Vanadium  (V)  is  a  gray  metal  with  a  silver-like  metallic  luster. 
It  is  not  tarnished  by  air  or  water  at  ordinary  temperatures.  Spe-, 
cific  gravity  5.6.  Very  hard,  scratches  quartz.  It  is  a  rare  element 
found  in-  vanadates  or  salts  of  vanadic  acid. 

The  principal  commercial  ores  are  roscoelite,  vanadinite,  patronite, 
carnotite  and  descloizite.  | 

Roscoelite.     Vanadium  mica.     Hydrous  silicate  of  vanadium,  alum-  j 
inum   and  potassium.     Color   dark  brownish   or   green,   perfect  basal 
cleavage,  pearly  luster.     Soft  (hardness  about  2.0),  and  light  (specific 
gravity  2.9).     Found  in  small  scales  or  plates.     Contains  from  20% 
to  29%  VoO,. 

Vanadinite.  Vanadate  of  lead  and  chlorine.  Contains  19.4%  VoO- 
and  73%  Pb.  Color  deep  ruby  red,  sometimes  yellow.  Resinous  or 
adamantine  luster.  Hardness  3.0.  Specific  gravity  6.7-7.2.  Brittle. 
Generally  occurs  in  small  prisms.     Hollow  crystals  are  common. 

Patronite.  Vanadium  sulphide  (VS^).  Contains  25.5%  V,  and 
74.5%  S.  Dark  green  to  black  in  color.  Hardness  3.5.  Specific 
gravity  2.6.     Generally  amorphous  with  conchoidal  fracture. 

Carnotite.  A  comparatively  new  mineral  discovered  in  Avestern 
Colorado.  Has  a  complex  formula,  containing  uranium,  vanadium, 
potassium,  calcium  and  other  elements.  A  good  ore  of  vanadium. 
Color  yellow.  Very  soft.  Dull  luster.  Occurs  as  a  powder  in  cava- 
ties  in  sandstone. 

Descloizite.  Vanadate  of  lead  and  sometimes  zinc  and  copper.  Con- 
tains 22.7%  VoO-.  Color  red  to  yellowish,  brown  or  green.  Greasx 
luster.     No  cleavage.     Hardness  3.5.     Gravity  6.2. 

Distribution. 

No  commercial  production  of  vanadium  has  yet  been  made  in  Cali- 
fornia. Occurrences  have  been  noted  at  Camp  Signal  near  Goffs  in 
San  Bernardino  County.  Recent  discoveries  are  reported  from  Kern 
County;  also  from  Riverside  County,  in  the  29  Palms  District. 

The  domestic  supply  comes  from  Colorado,  Nevada  and  Utah.  Ores 
are  generally  found  associated  with  sedimentary  rocks,  sandstone,  clays 
and  shales.  Also  found  in  a  variety  of  forms  in  connection  with  gold, 
lead,  zinc  and  iron  ores. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  101 

Tests. 

Vanadium  minerals  when  treated  with  concentrated  hydrochloric 
acid  (HCl)  give  a  rich  brown  solution.  It  may  be  necessary  to  first 
fuse  the  mineral  with  sodium  carbonate  before  dissolving.  If  the 
clear  liquid  is  poured  off  into  another  test  tube,  and  a  strip  of  zinc 
or  tin  added,  the  solution  becomes  first  blue,  then  green  and  finally 
violet.  Also,  when  water  is  added  to  the  original  solution,  the  color 
changes  to  green  or  disappears.  If  dilute  acid  is  used  to  bring  tte 
mineral  into  solution  the  color  is  green  or  yellowish. 

Heated  with  borax  or  salt  of  phosphorous  in  the  oxidizing  flame  the 
bead  is  yellow  or  deep  amber,  changing  to  yellowish  green  or  colorless 
when  heated  in  the  reducing  flame. 

Metallurgy. 

Ores  containing  vanadinite  and  descloizite  may  be  concentrated  over 
tables,  by  the  ordinary  methods  because  of  the  cry'-stalline  nature  of 
these  minerals  and  the  high  specific  gravity  w^hich  the  lead  gives  them. 
In  the  case  of  roscoelite,  concentration  is  impossible.  Carnotite  has 
been  concentrated  by  air  blast  while  the  ore  is  being  crushed. 

Concentration  by  chemical  means,  using  both  alkalies  and  acids, 
has  been  successful,  but  the  processes  are  complicated. 

The  two  common  forms  in  which  the  concentrate  is  prepared  for 
use  in  the  manufacture  of  ferro-alloys  are,  vanadium-pentoxide  and 
ferrous- vanadate. 

The  finely  ground  concentrate  is  heated  in  a  reverberatory  hearth 
with  sodium  carbonate.  The  soda  slag  containing  the  vanadium  is 
leached  and  treated  by  several  chemical  processes  for  the  production 
of  the  pentoxide. 

The  raw  concentrate  may  be  leached  in  lead  lined  vessels  with 
sulphuric  acid,  and  by  decantation,  evaporation  and  ignition  vanadium 
pentoxide  is  obtained. 

Reduction  to  the  metallic  state  and  the  preparation  of  ferro-vana- 
dium  is  carried  on  in  the  electric  furnace  or  by  the  aluminothermic 
process. 


ZINC. 

Industrial  application  and  uses. 

Zinc  is  largely  used  in  the  form  of  sheets  for  roofing,  cornices,  pipes, 
etc.,  in  building  construction,  and  for  lining  tanks  and  other  com- 
mercial utensils.  Zinc  plates  are  extensively  used  in  electrical  bat- 
teries. Sheet  iron  dipped  into  molten  zinc  becomes  coated  and  makes 
the   so-called  'galvanized  iron.'     Wire   is  also   treated  in  this  way. 


102  CALIFORNIA    STATE    MINING   BUREAU. 

Zinc  is  largely  used  in  the  manufacture  of  protective  coatings  and 
paints.     Zinc  dust  is  used  in  chemistry  and  metallurgy.  I 

Anti-friction  metals  and  other  alloys  are  composed  largely  of  zinc.  ' 
Babbitt's  metal,  for  example,  containing  69%.     Brass  is  an  alloy  of 
copper  (65%)  and  zinc  (35%). 

Properties  and  ores. 

Zinc  is  a  bluish  white  lustrous  metal  whose  physical  properties  vary 
considerably  with  the  temperature.  At  ordinary  temperatures  it  is 
brittle,  but  when  heated  it  may  be  rolled  into  sheets  and  drawn  into 
wire  and  does  not  become  brittle  again  upon  cooling.  When  heated 
to  200°  C.  it  again  becomes  brittle  and  can  be  easily  pulverized.  It 
does  not  tarnish  in  dry  air,  but  ordinarily  becomes  coated  with  a 
dark  film.  Soft  (hardness  2.0),  specific  gravity  6.9-7.2.  The  chief 
ores  are  sphalerite,  smithsonite,  willemite,  calamine,  zincite  and  frank- 
linite. 

Sphalerite  (ZnS)  Zinc  sulphide.  Sometimes  called  'jack,'  and 
'rosin  jack.'  Zinc  blende.  Contains  67%  Zn,  33%  S.  Color  yellow, 
brown  or  black,  streak  white  to  yellowish  brown,  resinous  or  waxy  lus- 
ter, brilliant  when  broken,  brittle,  hardness  3.5-4.0,  specific  gravity  1.0. 
Sometimes  transparent  or  translucent.  Typically  associated  with 
galena. 

Smithsonite  (ZnCOg)  Zinc  carbonate.  'Dry  bone.'  Contains 
ZnO  64.8%,  CO2  35.2%.  Color  gray,  grown  or  green,  vitreous  luster, 
brittle,  hardness  5.0,  specific  gravity  4.4.  Occurs  in  drusy  crystals  or 
massive,  often  bone-like,  associated  with  silver  lead  ores  and  the 
silicates  of  zinc. 

Willemite  (Zn2Si04)  Zinc  silicate.  Color  light  or  apple  green  to 
flesh  color,  brittle,  vitreous  luster,  hardness  5.5,  specific  gravity 
3.89-4.18,  basal  cleavage.     Occurs  massive  and  granular. 

Calamine     (HgZngSiOg)     Basic    or    hydrous    zinc    silicate.     Color  ^ 
white,  blue  or  brown,  vitreous  luster,  hardness  4.5-5,  specific  gravity 
3.4-3.5.     Occurs  in  drusy  masses  or  earthy.     Found  in  oxidized  por- 
tions of  zinc  veins. 

Zincite    (ZnO)    Zinc    oxide.     Contains    80.3%    Zn    and    19.7%    0.\ 
Color  deep  or  bright  red,  streak  orange  yellow,  brilliant  luster,  hard 
ness    4.0-4.5,    specific    gravity    5.68-5.74.     Perfect    ba^al    cleavage. 
Usually  occurs  in  foliated  masses.  i 

Franklimte  is  an  iron  oxide,  resembling  magnetite,  and  contains 
zinc  and  manganese. 


COMMERCIAL   MINERALS   OF    CALIFORNIA.  103 

Distribution. 

The  largest  production  in  California  in  1918  was  from  Shasta 
County,  followed  in  order  by  Inyo  and  San  Bernordino  counties.  In 
Shasta  County  the  zinc  ores  are  associated  with  copper,  while  those 
of  Inyo  and  San  Bernardino  are  associated  mostly  with  lead-silver 
ores.  Zinc  minerals  are  found  in  small  quantities  in  many  counties 
in  the  state.  Electrolytic  zinc  smelters  were  in  operation  by  the 
]\Iammoth  Copper  Mining  Company  at  Kennett,  Shasta  County,  and  by 
the  Bully  Hill  Copper  Mining  and  Smelting  Company  at  Winthrop, 
Shasta  County,  but  it  is  understood  that  these  are  now  closed. 

Tests. 

Zinc  volatilizes  when  heated  before  the  blowpipe  on  charcoal  and 
gives  a  canary  yellow  coating  of  zinc  oxide,  which  becomes  white  when 
cold.  Fragments  of  zinc  minerals  may  be  tested  in  this  manner. 
With  some  minerals  it  may  be  necessary  to  use  a  flux  of  one-half  volume 
of  sodium  carbonate.  The  test  requires  first  the  reduction  of  zinc 
to  the  metallic  state  and  then  its  volatilization,  hence  great  care  must 
be  taken  in  the  manipulation  of  the  blowpipe  flame,  in  order  that 
the  metallic  particles  are  not  blown  away.  If  the  charcoal  is  moistened 
with  cobalt  nitrate  before  making  the  test,  the  coating  will  have  a 
green  color  which  is  very  characteristic.  Infusible  or  light  colored 
zinc  minerals  when  powdered  and  made  into  a  paste  with  cobalt  nitrate 
and  heated,  assume  a  green  color. 

Metallurgy. 

The  process  of  zinc  smelting  which  has  been  in  general  use  in  this 
country  for  many  years,  is  as  follows:  The  ore  is  first  roasted  in 
open  hearth  furnaces  to  remove  most  of  the  sulphur.  It  is  then 
intimately  mixed  with  about  40%  of  fine  coal  and  placed  in  retorts 
made  of  excellent  quality  of  fire  clay.  These  retorts  are  from  four 
to  six  feet  long  and  eight  to  ten  inches  in  diameter  and  are  arranged 
in  layers  and  tiers  in  the  smelting  furnace,  each  furnace  containing 
from  200  to  300  of  these  retorts.  The  furnace  contains  several  fire 
places  and  is  fired  by  soft  coal  or  powdered  coal. 

At  1200°  to  1300°  Centigrade,  distillation  takes  place,  the  zinc 
vaporizes  and  passes  off  to  the  condensing  chambers  where  it  is 
condensed  into  molten  form.  The  complete  treatment  of  a  charge 
requires  about  twenty-four  hours  and  the  molten  zinc  is  drawn  from 
the  condensing  chamber  at  various  intervals.  At  the  end  of  the  treat- 
ment period,  the  temperature  is  raised  to  remove  the  last  traces  of 
zinc.     The  average  life  of  a  retort  is  about  40  charges. 


104  CALIFORNIA   STATE   MINING   BUREAU. 

Recently  great  progress  has  been  made  in  the  electrolytic  treatment 
of  zinc  ores.  This  method  is  especially  applicable  to  copper-zinc  ores, 
or  to  low  grade  ores.  The  method  of  treatment  consists  of  first  roast- 
ing the  ore  in  an  open  hearth  furnace,  then  leaching  with  sulphuric 
acid.  The  copper  is  precipitated  from  the  solution  by  zinc  dust  and 
the  metallic  zinc  obtained  by  electrolysis. 

Concentration  of  zinc  ores  by  flotation  is  now  being  practiced  quite 
extensively. 


COMMERCIAL   MINERALS   OF   CALIPORNLV.  105 


APPENDIX. 


PHYSICAL  PROPERTIES  OF  MINERALS. 
Under  physical  properties  the  following  are  here  explained: 

Hardness. 

The  place  given  a  mineral  in  a  scale  of  hardness,  now  in  general 
ii>e,  and  which  is  known  as  Moh's  scale.  It  is  as  follows:  (1)  Talc, 
(2)  Gypsum,  (3)  Calcite,  (4)  Fluorite,  (5)  Apatite,  (6)  Feldspar, 
f7)   Quartz,   (8)   Topaz,   (9)   Corundum,   (10)  Diamond. 

The  place  which  a  mineral  occupies  in  this  scale  is  determined  by  the 
ease  with  which  it  scratches,  or  with  which  it  is  scratched  by  the 
minerals  mentioned.  Thus,  if  upon  trial,  a  certain  mineral  is  found 
to  scratch  feldspar  but  in  turn  is  scratched  by  quartz,  it  would  have 
a  hardness  of  between  6  and  7  or  say  6.5.  In  testing,  a  sharp  point 
or  corner  of  one  mineral  should  be  used  upon  the  smooth  face  of 
another,  and  care  should  be  taken  to  distinguish  between  hardness  and 
brittleness.  Brittle  minerals  often  crumble  or  break  down,  and  appear 
to  be  soft,  whereas  if  due  care  is  taken  ihej  are  found  to  be  a  great 
deal  harder  than  it  would  seem.  Also,  in  some  cases  it  will  take  close 
observation  to  distinguish  between  a  mark  or  streak  left  by  one  mineral 
on  another  and  an  actual  scratch. 

Common  methods  of  testing  for  hardness  are  with  the  finger  nail, 
which  scratches  talc  easily  and  gypsum  with  difficulty;  a  copper  coin 
whose  hardness  is  3.0;  pin  point,  hardness  about  3.5;  knife  blade 
hardness  a  little  over  5;  and  ordinary  window  glass,  hardness  5.5; 
quartz  crystal  hardness  7.0;  small  piece  of  corundum,  hardness  9.0. 
With  practice  the  hardness  of  a  mineral  can  be  closely  approximated 
by  the  ease  with  which  it  is  scratched  with  a  knife  blade. 

Specific  gravity. 

The  specific  gravity  of  a  substance  is  the  ratio  of  its  weight  to  the 
weight  of  an  equal  volume  of  water.  The  weight  of  water  (62.5  pounds 
per  cubic  foot)  is  taken  as  one.  Thus  metallic  lead  has  a  specific 
gravity  of  11.37,  whicli  means  that  it  is  11.37  times  heavier  than  water. 
Careful  laborator^^  work  is  necessary  to  accurately  determine  the  spec- 
ific gravity  of  a  mineral  sample,  but  with  practice,  and  with  the  aid 
of  several  common  substances  or  minerals,  whose  specific  gravities  are 
known,  close  approximations  can  be  made.  Common  substances  with 
specific  gravities  are  as  follows:  Borax,  1.7;  sulphur,  2.1;  halite 
(common  salt),  2.1;  serpentine,  2.5-2.6;  quartz  and  granite,  2.6;  talc, 


106  CALIFORNIA    STATE    MINING    BUREAU. 

2.8;  magnesite,  3.0;  chromite,  4.2-4.6;  barite,  4.5;  pyrite,  5.0;  cuprite, 
6.0;  scheelite,  6.0;  iron,  7.3;  galena,  7.6;  copper,  8.8;  silver,  10.5; 
gold,  19.3. 

Color. 

The  color  of  a  mineral  may  be  very  distinct  and  characteristic,  as 
in  the  case  of  cinnabar,  or  it  may  vary  through  almost  every  shade 
as  is  shown  by  fluorite,  quartz  and  tourmaline.  In  observing  the 
color,  care  should  be  taken  to  obtain  a  fresh,  unaltered  sample.  Dark 
minerals  often  require  a  close  examination  for  a  distinguishing  shade 
of  deep  green,  brown,  etc.,  and  a  small  or  thin  piece  will  often  bring 
out  a  distinct  color  in  a  mineral  that  appears  absolutely  black  and 
opaque.  Frequently  a  mineral  is  colored  by  some  foreign  substance 
with  which  it  is  merely  mechanically  mixed,  and  in  this  case  the  color 
is  misleading.  I 

Streak.  ^ 

The  streak  of  a  mineral  is  merely  the  color  of  the  very  fine  powder. 
This  is  easily  obtained  by  rubbing  the  sample  on  a  piece  of  white 
unglazed  porcelain.  The  streak  often  gives  a  delicate  shade  not  shown 
in  the  lump  sample  of  the  mineral. 

Luster. 

The  luster  of  a  mineral  is  the  appearance  of  the  surface  due  to 
its  reflection,  refraction  or  absorption  of  the  light.  Common  lusters 
defined  are  as  follows: 

Adamantine,  the  brilliant  luster  of  the  diamond.  Shown  by  only 
a  few  other  gem  stones,  and  a  few  minerals  such  as  cinnabar  and 
cerussite. 

Vitreous,  glassy,  like  the  luster  of  glass. 
Besinous,  having  the  appearance  of  resin.     As  sphalerite. 
Greasy  or  oily,  as  if  the  mineral  had  a  thin  coating  of  oil  over  it. 
Pearly  J  like  mother  of  pearl. 
Silky,  like  a  skein   of  silk.     Observed  on  minerals  which  have   a 
fibrous  structure. 

Metallic,  the  characteristic  luster  of  the  metals  as  silver,  lead  or 
copper,  and  many  common  ores  as  pyrite,  galena,  etc.  Under  thia 
head  are  included  those  minerals  which  are  opaque. 

Suhmetallic,  dark  colored  minerals  which  have  a  somewhat  shiny 
appearance,  yet  cannot  be  said  to  have  the  true  luster  of  the  metals. 
Chromite  is  an  example. 


COMMERCIAL   MINERALS   OF   CALIFORNIA.  107 

Cleavage. 

Many  minerals  have  a  tendency,  due  to  crystallization,  to  break 
readily  in  certain  directions,  and  when  thus  broken  present  smooth 
surfaces,  resembling  crystal  faces.  This  property  is  called  cleavage. 
Good  cleavage  may  be  exhibited  in  only  one  direction,  or  in  several 
directions,  and  it  may  be  a  great  deal  more  distinct  in  one  direction 
than  in  another.  Direction  of  cleavage  may  be  indicated  by  the 
presence  of  minute  cracks  through  the  crystals  or  may  often  be  easily 
determined  by  striking  the  mineral  a  sharp  quick  blow  with  a  hammer. 

The  most  common  cleavages  are  cubic,  as  shown  by  galena,  rhomha- 
Jedral  as  in  calcite,  hasal  as  in  the  micas,  prismatic  when  produced 
with  equal  ease  in  two  directions,  parallel  to  certain  faces,  as  in 
amphibole. 

structure. 

The  common  form  or  appearance  of  a  mineral,  due  to  crystallization, 
or  absence  of  crystal  form.     Common  structures  are: 

Granular.  The  structure  of  a  mineral  which  consists  of  an  aggre- 
gate of  small  crystalline  particles  of  about  the  same  size. 

Compact  or  earthy.     Like  clay. 

Massive.  When  no  crystal  faces  can  be  seen,  although  the  mineral 
may  possess  a  crystalline  structure. 

Amorphous.     When  no  trace  of  crystalline  structure  exists. 

Columnar.     Made  up  of  columns  or  prisms  nearly  parallel. 

Fibrous.  Fine  fibres  or  shreds  arranged  in  parallel  groupings,  as 
asbestos. 

Schistose.  The  flattened  or  banded  appearance  of  some  metamor- 
phic  rocks,  due  to  great  pressure. 

Foliated.  When  a  mineral  may  be  separated  into  flat  plates,  of 
more  or  less  irregularity  in  shapes  and  thickness. 

Micaceous.  Like  foliated,  only  more  perfect.  May  be  split  easily 
into  exceedingly  thin  sheets,  as  mica. 

Radiated.  When  columns  or  fibres  radiate  from  central  points,  as 
in  pectolite. 

Reinform  of  m^ammillary.  Smooth,  rounded,  interlocking  or  over- 
lapping masses,  grouped  in  kidney  shapes,  as  in  some  varieties  of 
hematite. 

Botryoidal  a7id  globular.  Groupings  of  small  rounded  or  spherical 
nodules,  more  or  less  interlaced  or  overlapped,  as  in  smithsonite. 

Stalactitic.     Icicle,  or  pendant  like. 


108  CALIFORNIA   STATE   MINING   BUREAU. 

Porous,  cellular,  vesicular,  pumiceous.  Full  of  small  irregular 
cavities. 

Fracture. 

Some  minerals  possess  a  characteristic  fracture  when  broken,  such 
as  obsidian  or  volcanic  glass.  This  shows  a  smooth  curved  surface 
resembling  a  shell,  and  is  said  to  have  a  conchoidal  fracture.  Other 
common  fractures  are  uneven,  when  rough  or  irregular,  Jiackly,  when 
jagged,  and  splintery  when  the  substance  breaks  into  splinters  or 
needles. 

Other  physical  properties. 

Other  physical  properties  of  metals,  ores  or  minerals  are  as  follows: 

Malleable,  when  it  can  be  hammered  into  plates. 

Ductile,  when  it  can  be  drawn  into  a  fine  wire. 

Sectile,  when  it  can  be  cut  with  a  knife. 

Flexible,  when  it  bends  easily,  but  does  not  regain  its  original 
position. 

Elastic,  when  it  bends  easily,  but  springs  back  into  position. 

Brittle,  when  it  breaks  into  pieces  under  slight  pressure. 

APPARATUS  FOR  TESTS. 

A  short  description  is  here  given  of  the  apparatus  and  methods 
mentioned  under  the  tests  for  the  different  minerals.  Three  methods 
will  cover  the  tests  as  mentioned  in  this  bulletin:  first,  observation  ' 
of  the  physical  properties  or  peculiarities  of  the  minerals  or  ores; 
second,  tests  with  acids  or  solutions;  third,  tests  by  heating,  igniting, 
or  fusing. 

The  physical  properties  are  described  under  that  heading. 

In  regard  to  tests  with  acids  care  should  be  exercised  in  handling, 
heating,  etc.  Do  not  add  cold  water  to  very  hot  solutions.  Test 
tubes  containing  solutions  should  be  heated  gently  and  not  thrust 
directly  into  the  flame  and  held  there.  The  mouth  of  the  tube  should 
always  be  held  away  from  the  face.  Heating  over  a  piece  of  ordinary 
fine  wire  screen  will  prevent  breakage.  Only  a  very  small  amount  of 
powdered  mineral  need  be  used  for  a  test.  Usually  an  amount  that 
can  be  picked  up  on  the  point  of  an  ordinary  knife  blade  will  suffice, 
and  only  enough  acid  should  be  used  to  cover  the  mineral  well.  In 
general,  for  minerals  without  metallic  luster,  hydrochloric  acid  is  the 
most  convenient  solvent,  while  for  sulphides  and  arsenides,  which 
usually  have  a  metallic  luster,  nitric  acid  is  best.  Strong  evolution 
of  gas  should  be  guarded  against. 


COMMERCIAL    MINERALS   OP    CALIFORNIA.  109 

In  the  test  by  heating,  it  is  best  to  have  access  to  an  ordinary  gas 
jet,  but  many  of  the  tests  may  be  made  by  heating  in  other  simple 
ways  as  mentioned.     Apparatus  mentioned  is  described  as  follows: 

B  1(71  sen  hxirner.  This  consists  simply  of  a  metal  tube  about  one- 
half  inch  in  diameter  and  six  inches  high,-  mounted  on  a  base  and 
attached  to  the  gas  jet  by  means  of  a  hose.  The  gas  enters  at  the 
bottom  and  is  mixed  with  air  which  comes  through  two  holes  in  the 
tube  near  the  entrance  jet.  A  cylindrical  ring  is  provided  to  fit  over 
the  tube  with  holes  corresponding  to  the  air  holes  in  the  tube,  and 
with  which  the  supply  of  air  can  be  regulated.  The  mixture  of  gas 
and  air  should  be  such  that  the  burner  gives  a  blue  flame  with  a 
distinctly  outlined  inner  cone.  The  outer  portion  is  the  oxidizing 
flame,  while  the  inner  cone  is  the  reducing  flame. 

The  blowpipe.  The  common  blowpipe  consists  of  a  tapering  brass 
tube,  about  eight  or  ten  inches  in  length  and  of  small  diameter,  vary- 
ing from  one-quarter  to  one-thirty-second  of  an  inch.  The  lower, 
smaller  end  is  curved  and  terminates  in  a  small  bulb  in  which  there 
is  an  opening  as  large  as  a  pin  point.  The  blowpipe  is  used  in  con- 
junction with  the  Bunsen  burner  flame.  The  tube  is  placed  in  the 
mouth,  the  cheeks  extended  and  a  continual  and  steady  current  of  air 
forced  through.  The  tip  is  placed  sidiewise  in  the  flame  in  such  a 
manner  that  a  jet  of  flame  is  forced  to  one  side  and  downward  upon  the 
sample  of  mineral,  which  is  usually  carried  on  a  piece  of  charcoal. 
The  flame  produced  in  this  manner  is  intensely  hot,  and  is  similar  to 
that  of  the  Bunsen  burner,  the  outer  cone  being  the  oxidizing  flame, 
while  the  inner  one  is  the  reducing  flame.  Some  skill  and  practice  is 
necessary  in  order  that  the  blowpipe  be  operated  successfully. 

Closed  tubes  are  made  from  ordinary  glass  tubing  from  one-eighth 
to  one-quarter  inch  in  diameter,  cut  into  lengths  of  three  or  four 
inches  and  sealed  at  one  end.  They  are  used  for  heating  substances 
with  slight  access  of  air. 

Open  tubes  are  pieces  of  ordinary  glass  tubing  about  six  inches 
long,  slighth'  bent  in  the  middle  and  open  at  both  ends.  Used  for 
heating  substances  in  free  circulation  of  air. 


110  CALIFORNIA   STATE   MINING   BUREAU. 


BIBLIOGRAPHY. 

Publications  of  the  United  States  Geological  Survey,  Department  of  the  Interior, 

Washington,   D.  C. 

The  following  is  a  brief  summary  of  the  publications  of  the  United  States 
Geological  Survey,  complete .  catalogues  and  indexes  of  which  will  be  found 
at  libraries  where  such  publications  are  on  file,  or  may  be  obtained  by  writing 
to  the  department  at  Washington,  as  indicated  above.  Many  of  the  publications 
are  for  free  distribution. 

Annual   reports. 

Issued  by  the  Director  of  Survey  to  the  Secretary  of  the  Interior  at  the  end 
of  every  fiscal  year.  Essentially  a  report  on  the  work  accomplished  during  the 
year,  giving  results  of  special  investigations  or  research  work ;  a  brief  abstract 
of  publications  of  the  year,  and  a  summary  of  work  by  branches  and  divisions. 
Also  gives  maps  showing  the  progress  of  topographic  and  geologic  surveys. 

Monographs. 

Exhaustive  treatises  or  reports  on  research  work  dealing  with  many  special 
subjects,  or  investigation  of  certain  districts,  along  the  lines  of  geology,  paleon- 
thology,    etc.,    written    by    some    of   the    foremost   scientists. 

Professional  papers. 

Detailed  descriptions  of  particular  regions,  or  special  subjects,  coverinii*  a  wide 
range  of  subjects  as  regards  ore  deposits,  geology,  water  supply,  forests,  plants 
and   animals,   etc.     Often   accompanied   by  plates   and   maps. 

Bulletins. 

Discussions,  descriptions  and  research  work  covering  a  great  variety  of  subjects 
such  as  mineralogy,  chemistry,  geology  and  various  ores,  and  numbering  at  present 
over  700. 

Water  supply  papers. 

Reports  on,  and  results  of,  surveys  on  water  supply,  in  all  parts  of  the  United 
States,    dealing   with    surface    and    underground    waters,    rivers,    drainage,    etc. 

Mineral  resources  of  the  United  States. 
Part  I.  Metai>s.     Issued  annually. 

Describes  in  detail  the  production,  value,  etc.,  of  all  the  metals  found  in  the 
United  States.  Gives  production  by  states  and  describes  the  principal  pro- 
ducing localities,  characteristic  occurrences  in  the  different  districts,  exports, 
imports,  gives  data  on  commercial  importance,  uses,  as  well  as  total  world  pro- 
duction. 

Separate  pamphlets  are  issued  on  certain  minerals  or  groups  of  minerals  which 
are  naturally  associated,  or  Avhose  production  is  confined  principally  to  a  certain 
district. 

Part    II.  Non-Metals.     Issued   annually. 
Same    as   above,    only    deals   entirely    with    the    non-metals.     Separate    pamphlets 
on  each  mineral,  issued  as  soon  as  possible  after  data  is  procured  and  before  they 
are    incorporated    into    final    bound    volume.     These    are    available    for    distribution 
from  August  to  December  of  the  succeeding  year. 

Special  publications. 

A  few  preliminary  reports,  and  results  of  surveys  in  Alaska. 

Topographic  and  geologic  atlas  of  the  United  States. 

When  completed  this  will  comprise  a  survey  of  the  entire  United  States,  showing 
in  detail  the  topography  and  the  geology.  The  maps  are  of  convenient  size  and 
bound  in  folios,  along  with  descriptive  matter  on  the  district  treated.  Each 
map   represents   an    area   called   a   quadrangle    which    is    bounded    by    parallels   of 

1             1 
latitude  and  meridians  of  longitude.      Three   scales  are  used,   i.  e., •  

250,000  125,000 
1 

and 

62,500. 
The  separate  sheets  on  topography  or  geology  may  also  be  obtained.     Maps  are: 
issued  showing  areas  which  have  been  completed. 


COMMERCIAL    MINEILVLS   OF    CALIFORNIA.  Ill 

Publications  of  the   Bureau  of  Mines,  Department  of  the  Interior, 
Washington,   D.  C. 

(Catalogues  and  indexes  of  publications  may  be  obtained  by  addressing  the 
Department  as  above,  or  may  be  consulted  at  technical  libraries.) 

Bulletins. 

Scientific  discussions,  experiments  and  information  on  a  great  variety  of 
subjects   pertaining   to   mining   and    metallurgy,    numbering   at   present   about   200. 

Technical  papers. 

Comparatively    short    discussions    on    many    special    subjects    relating    to    mining. 

Publications  of  the  California  State  Mining  Bureau. 

A  list  of  publications  is  given  in  the  back  of  this  bulletin  and  a  Catalogue  is 
also  issued,  free  of  charge,  which  gives  a  short  description  of  all  bulletins, 
reports,  etc. 

REFERENCES. 

Particular  reference  was  made  in  the  preparation  of  this  bulletin  to  the  following : 
Bulletin  No.  67,  Minerals  of  California. 

Description  of  all  minerals  found  in  California  with  localities  where  each  occurs. 
Lists  of  principal  ores  of  the  commercially  important  minerals,  and  lists  of  minerals 
found  in  each  county.     Bibliography  on  California  minerals. 

California    Miner^vl    Production    for    1915,    1916,    1917    and    1918,    Bulletins 
Nos.  71,  74,  83  and  86,  respectively. 
Statistics  on   the  production  and  value  of  minerals  in  California  for  each  year, 
together   with   other  information  on   uses,   etc.     Gives  production   by  counties,  and 
also   contains    county    maps. 

Preliminary  Report  No.  3,  Manganese  and  Chromium. 

Description  of  the  ores,  uses,  occurrence  and  prices,  with  list  of  producers  and 
buyers  of  manganese  and  chromium  in  California,  with  a  short  chapter  on  the 
concentration  of  chrome  ores. 

Preliminary  Report  No.  4,  Tungsten,  Molybdenum  and  Vanadium. 

Gives  properties,  ores,  uses,  occurrence,  price,  producers  and  buyers  of  metals 
mentioned. 

Preliminary  Report  No.  5,  Antimony,  Graphite,  Nickel,  Potash,  Strontium,  Tin. 
Gives  properties,   ores,   uses,   occurrence,   prices,   producers  and  buyers  of  metals 
mentioned. 

Also  : 

Outlines  of  Industrial  Chemistry.     By  F.  H.  Thorp,  PJi.D.     1905. 

The  Non-metallic  Minerals.     George  P.  Merrill.     1904. 

Determinative     Mineralogy     and     Blowpipe     Analysis.     George    J.     Brush     and 

Samuel  L.  Penfield,  1906. 
Manual  of  Mineralogy  and  Petrography.     James  D.  Dana.     1918. 
Descriptive  Chemistry.     Lyman  C.  Newell,  Ph.D.     1906. 
Mineral    Deposits.     Waldemar   lAndgren.     1913. 

STANDARD  TEXT  OR  REFERENCE  BOOKS  ON   MINERALS  AND  ROCKS. 

Catalogues  of  the  standard  reference  and  textbooks  on  minerals  and  ro(^s, 
mining,  geology,  assaying,  metallurgy,  prospecting,  etc.,  giving  short  descriptions 
of  each  work,  may  be  obtained  from  the  following  publishers : 

Mining  and  Scientific  Press,  Technical  Book  Department,  420  Market  street, 
San   Francisco. 

John  Wiley  and  Sons,  Publishers,  New  York. 

McGraw  Hill  Book  Company,  Tenth  Avenue  and  Thirty-sixth  street,  New  York. 

D.  Van  Nostrand  Company,  New  York. 

Macmillun   Company,   New   York. 


112  CALIFORNIxV   STATE    MINING   BUREAU. 

SELECTED  BIBLIOGRAPHY   ON  MINERALOGY  AND   THE 
IDENTIFICATION  OF  MINERALS. 

Prepared  by  R.  W.  Gannett  and  C.  T.  Robertson. 

Published  by  the  Bureau  of  Mines,  Department  of  the  Interior. 

Bramble,  C.  A.  The  A  B  C  of  mining,  1898,  183  pages.  Rand,  McNally  and 
Company,  Chicago,  111.  $1.00.  Prospecting,  methods  of  testing  and  assaying 
ores,  surveying,  camp  life,  and  general  mining  are  briefly  discussed  in  simple 
language.  Although  much  of  the  book  is  now  out  of  date,  the  discussion  on 
prospecting  and  camp  life  is  particularly  valuable. 

Brush,  G.  J.  Manual  of  determinative  mineralogy,  with  an  introduction  on  blow- 
pipe analysis ;  revised  and  enlarged  by  S.  L.  Penfield.  Edition  16,  1909,  312 
pages.  John  Wiley  and  Sons,  New  York,  N.  Y.  $3.50.  A  standard  reference 
book  for  blowpipe  determination  of  minerals. 

Bnrdick,  A.  J.  Valuable  minerals  ;  how  to  find  and  know  them.  1916,  42  pages. 
Gateway  Publishing  Company,  Beaumont,  California  $0.50.  A  non-technical 
pamphlet  giving  excellent  notes  on  prospecting  and  testing  of  minerals.  It  does 
not  pretend  to  be  comprehensive. 

Butler,  G.  Af.  Handbook  of  mineralogy,  blowpipe  analysis,  and  geometrical  crystal- 
lography. 1916,  546  pages.  John  Wiley  and  Sons,  New  York,  N.  Y.,  $3.50. 
This  is  a  combination  of  three  books  issued  previously  as  follows :  Pocket 
handbook  of  minerals.  Edition  2,  1912,  311  pages,  $2.50 ;  Pocket  handbook  of 
blowpipe  analysis.  1910,  80  pages,  $0,75 ;  Manual  of  geometrical  crystallography, 
(treating  solely  of  those  portions  of  the  subject  useful  in  the  identification  of 
minerals.     Edition  1,  1918,  155  pages,  $1.50. 

Cahen,  Edward,  and  Wooten,  W.  O.  Mineralogy  of  the  rarer  metals,  a  handbook 
for  prospectors.  1912,  211  pages,  J.  B.  Lippincott  Company,  Philadelphia,  Pa. 
$2.50.  Discusses  all  the  rare  metals  under  the  headings  of  the  detection,  proper- 
ties, metallurgy,  industrial  application,  annual  production,  and  value. 

Cox,  S.  H.  Prospecting  for  minerals.  Edition  7,  1918,  260  pages,  J.  B.  Lippin- 
cott Company,  Philadelphia,  Pa.  $2.25.  Hints  on  geology,  a  description  of 
properties  of  minerals,  tables  of  determinations,  and  a  discussion  of  nonmetallic 
minerals,  or  ores,  and  of  fuels.  This  book  is  probably  the  least  technical  of 
any  of  those  named  in  this  list. 

Daly,  R.  A.  Ig-neous  rocks  and  their  origin.  1914,  563  pages.  McGraw-Hill 
Book  Company,  Incoi-porated,  New  York,  N.  Y.  $4.00.  A  standard  reference 
book  on  the  origin  of  igneous  rocks  and  their  petrologic  characters, 

Dana,  E.  8.  Minerals,  and  how  to  study  them.  Edition  2,  1897,  380  pages. 
John  Wiley  and  Sons,  New  York,  N.  Y.  $1.50.  A  book  for  beginners  in 
mineralogy, 

Duna,  E.  8.  Textbook  of  mineralogy,  with  an  extended  treatise  on  crystallography 
and  physical  mineralogy.  New  edition,  entirely  rewritten  and  enlarged,  1916, 
593  pages.     John  Wiley  and   Sons,  New  York,  N.  Y.  $1.25. 

Eakle,  A.  8.  Mineral  tables  for  the  determination  of  minerals  by  their  physical 
properties.     1904,    73    pages.     John    Wiley   and    Sons,    New   York,    N.   Y,   $1.25. 

Erni,  Hen\ri.  Mineralogy  simplified,  revised  by  Amos  P.  Brown.  Edition  4,  1908, 
414  pages.  H.  C,  Baird  and  Company,  Philadelphia,  Pa,  $2.50.  Easy  methods 
of  identifying  minerals,  including  ores.  Contains  physical  tables  for  the  determi- 
nation of  minerals  by  their  physical  characters. 

Ford,  W.  E.  Dana's  manual  of  mineralogy  for  the  student  of  elementary  miner- 
alogy, the  mining  engineer,  the  geologist,  the  prospector,  the  collector,  etc. 
Edition  13,  revised,  1916,  460  pages.  John  Wiley  and  Sons,  New  York,  N.  Y. 
$2.00.     A  standard  textbook. 

Frazer,  Persifor,  and  Brown,  A.  P.  Tables  for  the  determination  of  minerals  by 
physical  properties  ascertainable  with  the  aid  of  a  few  field  instruments. 
Edition  6,  1910,  125  pages.  J.  B.  Lippincott  Company,  Philadelphia,  Pa.  $2.50. 
'l^'lls  how   to  identify  minerals  principally  by  their  outward  characteristics. 

(ivorge,  R.  D.  Common  minerals  and  rocks;  their  occurrence  and  uses.  Colorado 
Geological  Survey  Bulletin  No.  12,  1917,  463  pages.  A  descriptive  mineralogy, 
rather  technical  in  its  form.  A  discussion  of  the  main  rock  types  is  also  given. 
Until  the  edition  is  used  up,  a  copy  can  be  obtained  free  from  the  Colorado 
Geological  Survey,  Boulder,  Colo. 

Hatch,  F.  H.  Mineralogy.  Edition  4,  1912,  253  pages.  The  Macmillan  Company, 
New   York,    N.   Y.   $1.40.     A   standard   textbook. 


COMMERCIAL   MINERALS    OF    CALIFORNIA.  113 

Kvmp,  J.  F.  Handbook  of  rocks,  for  use  without  the  microscope.  Edition  5,  1911, 
272  pages.  D.  Van  Nostrand  Company,  New  York,  N.,  Y.  $1.50.  Gives  a 
glossary  of  the  names  of  the  rocks.  It  is  a  standard  textbook  and  guide  in  field 
classification  of  rocks,  for  students,  mining  men  and  geologists.  Contains  glos- 
sary of  the  names  of  rocks  and  othen  lithological  terms. 

Kraus,  E.  H.  and  Hunt,  W.  F.  Tables  for  the  determination  of  minerals  by 
means  of  their  physical  properties,  occurrences,  and  associates,  1911,  254  pages. 
McGraw-Hill  Book  Company,  Incorporated,  New  York,  N.  Y.  $2.00.  A  standard 
reference  book. 

Miller,  W.  G.  Minerals  and  how  they  occur,  a  book  for  secondary  schools,  and 
prospectors.     1906,    252   pages.     Copp,    Clark,    Ldmited,   Toronto,    Canada. 

Moses,  A.  J.,  and  Parsons,  C.  L.  Elements  of  mineralogy,  crystallography,  and 
blowpipe  analysis  from  a  practical  standpoint.  Edition  5,  1916,  631  pages. 
D.  Van  Nostrand  Company,  New  York,  N.  Y.  $3.00.  A  standard  reference 
book  including  a  description  of  all  common  or  useful  minerals,  their  formation 
and  occurrences,  the  tests  necessary  for  their  identification,  the  recognition  and 
measurement  of  their  crystals,  and  their  economic  importance  and  uses  in  the 
arts. 

Oshorn,  H.  S.  Prospector's  field  book  and  guide  in  the  search  for  and  the  easy 
determination  of  ores  and  other  useful  minerals.  Edition  8,  1910,  401  pages. 
H.  C.  Biard  and  Company,  Philadelphia,  Pa.  $1.50.  An  excellent  book,  describ- 
ing many  tests  for  determining  minerals.  Some  of  the  tests  are  rather  difficult 
to   make   satisfactorily. 

Packer,  0.  H.  Prospector's  and  miner's  manual.  1913,  301  pages.  Brown  and 
Power  Stationery  Company,  San  Francisco,  California.  $3.00.  An  excellent 
book  for  prospectors  and  development  engineers  who  have  a  technical  training. 
Chapter  8  is  a  summary  of  the  mineral  districts  in  the  United  States  that  are 
particularly  promising. 

Phillips,  A.  H.  Mineralogy,  an  introduction  to  the  theoretical  and  practical  study 
of  minerals.     1912,  699  pages.     The  Macmillan  Company,  New  York,  N.  Y.  $3.75. 

Pirsson.  L.  V.  Rocks  and  rock  minerals.  1910,  414  pages.  John  Wiley  and 
Sons.  New  York,  N.  Y.  $2.50.  A  standard  textbook.  The  table  for  determining 
the  common  rocks    (pages  404-408)    is  particularly  valuable  and  useful. 

Schroder,  F.  C,  Stone,  R.  W.,  and  Sanford,  Samuel.  Useful  minerals  of  the 
United  States,  1917,  412  pages.  United  States  Geological  Survey  Bulletin 
No.  624.  Defines  nearly  600  names  of  minerals  and  lists  the  occurrence  of 
minerals  by  states  in  alphabetical  order.  Copy  can  be  obtained  by  applying  to 
Director,    United    States    Geological    Survey,    Washington,    D.    C. 

Tarr,  W.  A.  Tables  for  the  determination  of  the  common  minerals  and  rocks. 
1916.  28  pages.  University  Cooperative  Store,  Columbia,  Mo.  $0.40.  The 
tables  are  excellent  for  laboratory  reference  but  would  be  of  value  only  to  one 
understanding  the  terminology  used. 

BOOKS  ON  ECONOMIC  GEOLOGY. 

_To   supplement    the    foregoing   list,    three    standard    works    on    economic    geology 
might  be   mentioned,   as   follows : 
Emmos,   W.  H.     The  principles  of  economic  geology.     Edition  1,  1918,  606  pages. 

McGraw-Hill  Book   Company,   Incorporated,   New   York,   N.   Y.   $4.00.     Material 

relating  to  metallic  minerals  is  particularly  valuable. 
Lindfjren,    WaJdemar.     Mineral    deposits,    1913,    893    pages.     McGraw-Hill    Book 

Company,   Incorporated,   New  York,  N.  Y.  $5.00.     One  of  the  best  treatises  on 

economic  geology. 
Ries,  Heinrich.     Economic  geology.     Edition  4,  1916,  856  pages.     John  Wiley  and 

Sons,    New    York,    N.    Y.    $4.00.     Material    relating    to    nonmetallic   minerals    is 

particularly  valuable. 


8— 24S4 


11-lr  CAIJFORNIA    STATE    MINING   BLTREAU. 

BOOKS  ON  PROSPECTING. 

Underground  Treasures,  How  and  Where  to  Find  Tliem.  By  James  Orton. 
Plenry   Carey  Baird   and  Company,   Philadelphia,  1901. 

Contains  key  for  the  ready  determination  of  all  the  useful  minerals  within 
the  United  States ;  directions  for  determining  specimens ;  descriptive  list  of  use- 
ful minerals;  prospecting  for  diamonds,  gold,  silver,  copper,  lead,  and  iron; 
assay  of  ores ;  mineral  springs ;  discovery  of  gold  in  California ;  discowry  of 
silver   in    Nevada,    and    United    States    gold    and    silver   statistics ;    ore    deposits. 

Hidden  Mines,  and  how  to  find  them.  Contains  the  information  called  for  by 
the  ordinary  business  man,  who  is  interested  for  business  reasons  only.  By 
W.   Thos.  Newman.     Buffalo,  The  M.  Rogers  Publishing  Company,  1805. 

Contents  include  rock  formations  and  ore  deposits ;  how  to  distinguish  ores ; 
descriptions  of  native  metals  and  ores ;  other  minerals  of  commercial  value ; 
precious  stones  ;  practical  pointers. 

The  Prospector's  Manual,  for  the  Discovery  of  Quartz  and  Placer  Indications  of 
Gold  and  Silver  Mines,  also  a  description  of  mineral  bearing  rocks  ;  indications 
of  the  mineral  districts  in  all  the  New  England  states  and  the  neighboring 
provinces ;  the  characteristics  of  California,  Nevada  and  other  mines ;  simple 
methods  of  assaying  gold  and  silver  ores ;  and  the  glossary  of  scientific  and 
technical  terms.  By  Wm.  J.  Schofield.  W.  J.  Schofield  and  Company,  pub- 
lishers,  Boston,   1875. 

Prospector's  Pocket  Manual ;  Where  and  How  to  Find  Gold  and  Silvt^r  Mines. 
By  Henry  J.  Pomeroy.     Davis  and  Freegard,   St.  Louis,   1881. 

Covers  geology,  mineralogy ;  metallurgy ;  advice  to  prospectors ;  mining  laws 
and  rules,  compiled  for  the  Union  Pacific  Railway  Company.  Glossary  of  mining 
terms. 

Smith's  Handbook  of  Valuable  Minerals.  By  Frederick  H.  Smith,  member  A.  I. 
M.   E.     Baltimore,  1895. 

Contents  include  bottom  facts  and  bed  rocks ;  the  coal  measures  ;  oil  and  gas ; 
iron  and  manganese  ores ;  gold  and  silver  ores ;  copper  and  tin  ores  ;  lead  and 
zinc ;  nickel,  cobalt  and  chrome ;  antimony,  mercury,  platinum ;  gems  and  precious 
stones ;  building  and  paving  stones ;  cements  and  clays ;  salts  and  fertilizers ; 
mineral  paints ;  grits  and  spars ;  other  valuable  minerals ;  weights  and  measures ; 
companies  and  prices. 

Secrets  of  the  Rocks ;  or  The  Story  of  the  Hills  and  the  Gulches.  A  manual  of 
Hints  and  Helps  for  the  Prospector  and  Miner.  By  S.  M.  Frazier.  Denver, 
Colo.     Hall  and  Williams,  1905. 

Chemical  elements  and  mineral  compounds ;  physical  characteristics  and  classes 
of  minerals ;  rock  fissures  and  vein  formation,  contact  and  other  veins,  lodes 
and  wall  rock ;  locating  gold  bearing  ledges,  mineralogy  and  metallurgy  in  brief ; 
roasting  minerals  under  examination ;  surface  disintegration  of  ore  bodies ; 
nature's  ore  roasting  process ;  general  chemical  and  special  tests  for  minerals ; 
examination  of  mines  and  sampling ;  placer  mines  and  placer  mining ;  appliances 
for  saving  fine  gold  ;  river  mining ;  tracing  a  quartz  lode  ;  advice  to  prospectors ; 
rock  constituents  and  mineral  ores. 

The  Prospector's  Field  Book  and  Guide  in  the  Search  for  and  Easy  Determination 
of  ores  and  other  Useful  Minerals.  By  Prof.  II.  S.  Oshorn;  Philadelphia, 
Henry  Carey  Baird  and  Company,  1910. 

Contains  preliminary  instruction  in  geology  and  mineralogy  ;  the  blowpipe  and 
its  uses ;  crystallography ;  sui-veying ;  analyses  of  ores ;  special  mineralogy ; 
tellurium,  platinum,  silver;  copper;  lead  and  tin;  zinc,  iron,  molybdenum, 
titanium,  uranium,  vanadium ;  mercury  ;  bismuth,  nickel,  cobalt,  cadmium,  alumi- 
num, antimony,  manganese ;  various  useful  minerals,  gems  and  precious  stones, 
I)etroleum,  ozocerite,  asphalt,  peat ;  prospecting  by  means  of  electricity,  weights 
and  measures,  standard  values  of  gold  in  different  countries,  power  for  mills, 
boring,  glossary  of  mining  terms. 

The  A  B  C  of  Mining,  a  Handbook  for  Pi-ospectors.  By  Charles  A.  Bramble. 
Rand,   McNally   and  Company,  Chicago  and  New  York,   1898. 

The  contents  include  chapters  on  prospecting,  how  to  test  for  minerals,  blow- 
pipe tests;  economic  ores  and  minerals;  mining;  camp  life;  surveying;  floating 
a  company ;  medical  hints ;  dynamite ;  atomic  weights ;  miscellaneous  information. 


COMMERCIAL    MINERALS   OF    CALIFORNLV.  115 

Prospectiujr  for  Gold  and  Silver.  By  Arthur  Lakes.  Scrauton,  Pa.,  the  Colliery 
Engineer   Company,   1895. 

Contains  articles  on  prospecting — preparation  and  outfit  for  work;  the  pros- 
pector's historical  geology ;  paleontology  or  study  of  fossils ;  lithology  or  study 
of  rocks :  mineralogy ;  ore  deposits — theories  regarding  their  origin ;  various 
forms  of  ore  deposits ;  relation  of  veins  to  eruptive  forces ;  gold  placers ;  deep 
leads :  mining  regions,  showing  examples  of  ore  deposits ;  ore  deposits  in 
sedimentary  rocks ;  examining  and  sampling  mining  properties,  prospects  or  mines  ; 
salting  mines ;  prospector's  tools ;  elements  of  mining  law  relating  to  prospecting. 

Prospecting,  Locating  and  Valuing  Mines.  By  R.  H.  Stretch.  Published  by  the 
Scientific  Publishing  Company,  New  York  and  London,  1899. 

Contents  cover  chapters  on  mistakes  in  mining ;  what  constitutes  a  mine ;  rock 
forming  minerals  and  rocks ;  physical  character  of  mineral  deix)sits ;  origin  of 
veins :  filling  of  mineral  veins ;  influence  of  rocks  on  vein  filling,  mineral 
deposits  other  than  veins ;  prospecting ;  making  locations ;  patents  to  mining 
ground :  early  development  of  mines ;  ores ;  useful  earthy  minerals ;  coal ;  gold 
gravel  deposits ;  water  and  its  measurement ;  artesian  wells ;  useful  tables ; 
reference   books. 

The  Gold  Tracer ;  a  Practical  Guide  for  Prospectors  and  Miners.  By  Joseph  M. 
Clark.     Published  1899  at  Portland  Ore.,  by  John  Talbot. 

How  to  become  a  successful  pi"ospector  or  miner ;  ore  bodies ;  placer  gold ;  how 
to  pan  ;  tracing :  to  uncover  hidden  veins  ;  post  holes  ;  gold ;  a  test  of  ores — gold 
test :  tests  for  silver,  copper,  platinum,  nickel,  the  blowpipe ;  gold  in  pyrites : 
chlorination  ;  outfit  for  prospector ;  values  of  different  metals ;  composition  of 
minerals ;  history  of  quartz  mining ;  diagrams. 

The  Miner's  Geology  and  Prosi>ector's  Guide  for  Mining  Students,  Miners,  Pros- 
pectors and  Explorers.  By  Geo.  A.  C order;  London  and  New  York,  Spon  and 
Chamberlain,   1907. 

Geology  and  its  allied  sciences — geognosy,  lithology,  petrology  and  paleon- 
tology ;  properties  of  minerals ;  mechanical,  organic,  igneous  and  metamori^hic 
rocks,  divisions  of  the  earth's  crust ;  composition  of  soil ;  alternation  of  strata : 
fossil  remains;  non-fragmental  rocks,  crystalline  and  glassy  rocks,  compound 
rocks,  granites  ;  sedimentary  and  stratified  rocks ;  secondary  or  mesozoic,  tertiary, 
etc. 

Mineral  prospecting,  weights  and  measures ;  gold ;  where  gold  is  found,  value 
of  the  ore.  methods  of  recovery,  tools,  blasting ;  weight,  specific  gravity,  and 
values  of  ores  in  lode,  minerals  and  rocks ;  the  blowpipe ;  water  power,  air, 
windmills :  surveying,  assay  of  gold ;  useful  tables,  notes  and  formulae ;  systems 
of  crystallization  ;    paleontology. 

Prospecting  for  Gold  and  Silver.  Instruction  paper  issued  by  the  International 
Cx)rrespondence   Schools,    Scranton,   Pa.   1898. 

Preliminary  education  and  preparation;  use  of  fossils;  prospector's  outfit ; 
prosi>ecting  placer  deposits ;  locating  placer  claims ;  United  States  practice-area 
and  shape  of  placers,  knowledge  of  mineral  value ;  recording ;  staking ;  pros- 
pecting lodes  or  veins ;  float ;  sampling  the  outcrop ;  locating  lode  claims ;  tunnel 
sites;  mill  sites;  geology  of  ore  deposits;  rock  forming  minerals;  regions  most 
favorable   for  ore   deposits;    examples   of  prospecting  regions;    prospector's   tools. 

Valuable    Minerals,    How    to    Find    and    Know    Them.     By    Arthur    J.    Burdick. 

Published    by    the    Gateway    Publishing    Company,    Beaumont,    California,    1916. 

Contents    'nelude   chapters   on    how   to    find   minerals ;    how   to    test   rocks   and 

ores ;  gems  and  how  to  find  them ;  gold,  silver,  copper,  lead,  coal ;  other  valuable 

minerals;  use  of  the  blowpipe. 


PUBLICATIONS.  117 


PUBLICATIONS  OF  THE  CALIFORNIA  STATE  MINING 

BUREAU. 

Publications  of  this  Bureau  will  be  sent  on  receipt  of  the  requisite  amount.  Only 
stamps,  coin  or  money  orders  will  be  accepted  in  payment.  The  prices,  noted,  include 
delivery  charges  to  all  parts  of  the  United  States. 

Money  orders  should  be  made  payable  to  the  State  Mining  Bureau. 

Personal  checks  will  not  be  accepted. 

REPORTS. 
Asterisk  (*)   indicates  the  publication  is  out  of  print. 
♦Report  I.     Henry  G.   Hanks.     1880. 

♦Report         II.     Henry  G.  Hanks.     1882. 
♦Report       III.     Henry  G.  Hanks.     1883. 
♦Report        IV.     Henry  G.  Hanks.     1884. 
♦Report         V.     Henry  G.  Hanks.     1885. 
♦Report        VI.     Part  1.     Henry  G.  Hanks.     1886. 
♦Report        VI.     Part  2.     Wm.  Irelan,  Jr.     1886. 
♦Report      VII.     Wm.  Irelan,  Jr.     1887. 
♦Report    VIII.     Wm.  Irelan,  Jr.     1888. 
♦Report        IX.     Wm.  Irelan,  Jr.     1889. 
♦Report         X.     Wm.  Irelan,  Jr.      1890.  Price 

Report       XL     Wm.  Irelan,  Jr.     1892.     (First  biennial) $1.00 

♦Report      XII.     J.  J.   Crawford.     1894.      (Second  biennial) 

♦Report    XIII.     J.  J.  Crawford.      1896.      (Third  biennial) 

Chapters  of   State  Mineralogist's   Report,   Biennial   period,    1913-1914.   Fletcher 
Hamilton  : 
Mines  and  Mineral  Resources  of  Imperial  and  San  Diego  Counties. — F.  J.  H. 

Merrill.     1914 .35 

♦Mines  and  Mineral  Resources,  Amador,  Calaveras  and  Tuolumne  Counties — 

W.   B.   Tucker,   1915 

Mines   and   Mineral    Resources,    Colusa,    Glenn,    Lake,    Marin,    Napa,    Solano, 

Sonoma  and  Yolo  Counties — Walter  W.  Bradley.     1915 .50 

Mines  and  Mineral  Resources,  Del  Norte,  Humboldt  and  Mendocino  Counties — 

F.  L.  Lowell.     1915 .25 

Mines  and  Mineral  Resources,  Fresno,  Kern,  Kings,  Madera,  Mariposa,  Mer- 
ced, San  Joaquin  and  Stanislaus  Counties — Walter  W.  Bradley,  G.  C.  Brown, 

P.  L.  Lowell  and  R.  P.  McLaughlin.     1915 .50 

Mines  and  Mineral  Resources,   Shasta,  Siskiyou  and  Trinity  Counties — G.   C. 

Brown.      1915 .50 

Report  XIV.     Fletcher  Hamilton,  1915,  Biennial  period  1913-1914.      (The  above 

county  chapters  combined  in  a  single  volume) . 2.00 

Chapters  of   State  Mineralogist's  Report,   Biennial  Period,    1915-1916,   Fletcher 
Hamilton  : 
Mines  and  Mineral  Resources,  Alpine,  Inyo  and  Mono  Counties,  with  geological 
map — Arthur   S.    Eakle,   Emile   Huguenin,   R.    P.    McLaughlin,   Clarence   A. 

Waring.     1917 1.25 

Same  as  above,  without  geological  map .65 

Mines  and  Mineral  Resources.  Butte,  Lassen,  Modoc,  Sutter  and  Tehama  Coun- 
ties— W.  Burling  Tucker,  Clarence  A.  Waring.     1917 .50 

Mines  and  Mineral  Resources,  El  Dorado,  Placer,  Sacramento  and  Yuba  Coun- 
ties— W.   Burling  Tucker,   Clarence  A.  Waring.     1917 .65 

Mines  and  Mineral  Resources,  Los  Angeles,  Orange  and  Riverside  Counties — 

Frederick   J.    H.   Merrill.      1917 .50 

Mines  and  Mineral  Resources,  Monterey,  San  Benito,  San  Luis  Obispo,  Santa 
Barbara  and  Ventura  Counties — Walter  W.  Bradley,  Emile  Huguenin,  C.  A. 

Logan,  Clarence  A.  Waring.      1917 .65 

Mines  and  Mineral   Resources,   San   Bernardino  and  Tulare   Counties — H.   C. 

Cloudman,  Emile  Huguenin,  F.  J.  H.  Merrill,  W.  Burling  Tucker     1917 .65 

Report  XV.     Fletcher  Hamilton,  1918,  Biennial  period,  1915-1916.      (The  above 

county  chapters  combined  in  a  single  volume) 3.75 

Chapters    of    the     State    Mineralogist's     Report,     Biennial     Period     1917-1918. 
Fletcher  Hamilton  : 
Mines  and  Mineral  Resources  of  Nevada    County — Errol    MacBoyle.     1918 —        .75 
Mines  and  Mineral  Resources  of  Plumas   County — Errol    MacBoyle.     1918. —        ,50 
Mines  and  Mineral  Resources  of  Sierra     County — Errol     MacBoyle.     1918. .50 

BULLETINS. 

♦Bulletin     1.     Dessicated  Human  Remains. — Winslow  Anderson.      1888 

♦Bulletin     2.     Methods  of  Mine  Timbering. — W.  H.  Storms.     1894 

♦Bulletin     3.     Gas  and  Petroleum  Yielding  Formations  of  the  Central  Valley  of 

California. — W.  L.  Watts.     1894 

♦Bulletin     4.     Catalogue   of   California   Fossils    (Parts   2,    3,    4   and   5). — J.    G. 

Cooper.     1894 

♦Bulletin     5.     The  Cyanide  Process:  Its  Practical  Application  and  Economical 

Results.— A.   Scheidel.     1894 


118 


CALIFORNIA    STATE    .AIIXIXG   BUREAU. 


PUBLICATIONS    OF    THE    CALIFORNIA    STATE     MINING     BUREAU— Continued 


Asterisk  (*)  indicates  the  publication  is  out  of  print. 

Bulletin     6.     Califorrxia  Gold  Mill  Practices.— E.  B.  Preston.     1895 

•Bulletin     7.     Mineral   Production  of  California,   by   Counties,   1894. — Ciias.   G. 

Yale.      (Tabulated    sheet) 

♦Bulletin     8.     Mineral   Production  of  California,   by  Counties,   1895. — Chas.   G. 

Yale.      (Tabulated    sheet) 

♦Bulletin     9.     Mine  Drainage,  Pumps,  etc. — Hans  C.  Behr.     1896 

♦Bulletin  10.     A    Bibliography    Relating    to    the    Geology,    Palaeontology,    and 

Mineral  Resources  of  California. — A.  W.  Vogdes.     1896 

♦Bulletin  11.     Oil  and  Gas  Yielding  Formations  of  Los  Angeles,  Ventura  and 

Santa  Barbara  Counties. — W.   L.  Watts.      1896 

♦Bulletin  12.     Mineral   Production   of  California,   by   Counties,    1896. — Chas.   G. 

Yale.     (Tabulated  sheet) 

♦Bulletin  13.     Mineral   Production   of  California,   by   Counties,    1897. — Chas.   G. 

YqIo        r  TS-blll^tGd.   sllGGt  ^ —         

♦Bulletin  14.     Mineral   Production  of   California,   by  Counties,    1898. — Chas.~GT 

Yale.     (Tabulated  sheet) 

Bulletin  15.     Map  of  Oil  City  Oil  Fields,  Fresno  County. — J.  H.  Means 

♦Bulletin  16.     The  Genesis  of  Petroleum  and  Asphaltum  in  California. — A.   S. 

Cooper.     1899 

♦Bulletin  17.     Mineral   Production  of  California,   by  Counties,    1899. — Chas.   G. 

Yale.     (Tabulated  sheet)   

♦Bulletin  18.     The  Mother  Lode  Region  of  California. — W.  H.  Storms.      1900 

♦Bulletin  19.     Oil  and   Gas  Yielding  Formations   of  California. — W.   L.   Watts. 

1900 

♦Bulletin  20.     Synopsis    of    General    Report    of    State    Mining    Bureau. — ^W.    L. 

Watts.     1900 

♦Bulletin  21.     Mineral   Production   of  California,  by   Counties,   1900. — Chas.  G. 

Yale.     (Tabulated  sheet)   

♦Bulletin  22.     Mineral  Production  of  California  for  Fourteen  Years. — Chas.  G. 

Yale.      1900.      (Tabulated  sheet) 

Bulletin  Reconnaissance  of  the  Colorado  Desert  Mining  District. — Stephen 

Bowers.     1901 

Bulletin  23.     The  Copper  Resources  of  California. — P.  C.  DuBois,  F.  M.  Ander- 
son, J.  H.  Tibbits,  and  G.  A.  Tweedy.     1902 

♦Bulletin  24.     The  Saline  Deposits  of  California. — G.  E.  Bailey.     1902 

♦Bulletin  25.     Mineral   Production   of  California,   by   Counties,    1901. — Chas.   G. 

Yale.      (Tabulated  sheet) 

♦Bulletin  26.     Mineral   Production    of   California   for   Fifteen   Years. — Chas.   G. 

Yale.     1901.     (Tabulated  sheet) 

♦Bulletin  27.     The  Quicksilver  Resources  of  California. — Wm.  Forstner.     1903— 
♦Bulletin  28.     Mineral   Production   of  California,   by  Counties,    1902. — Chas.   G. 

Yale.      (Tabulated  sheet)   

♦Bulletin  29.     Mineral  Production   of   California  for   Sixteen   Years. — Chas.    G. 

Yale.     1902.      (Tabulated  sheet). 

♦Bulletin  30.     A  Bibliography  of  Geology,  Palaeontology,  and  Mineral  Resources 

of  California. — A.  W.  Vogdes.     1903 

♦Bulletin  31.     Chemical    Analyses    of    California    Petroleum. — H.     N.     Cooper. 

1903.     (Tabulated  sheet) 

♦Bulletin  32.     Production  and  Use  of  Petroleum  in  California. — P.  W.  Prutzman. 

1904 

♦Bulletin  33.     Mineral   Production  of   California,   by   Counties,   1903. — Chas.   G. 

Yale.      (Tabulated  sheet)   

♦Bulletin  34.     Mineral  Production  of  California  for  Seventeen  Years. — Chas.  G. 

Yale.     1903.      (Tabulated  Sheet) 

♦Bulletin  35.     Mines  and  Minerals  of  California,  for  1903. — Chas.  G.  Yale.     1904. 

(Statistical)   

♦Bulletin  36.     Gold  Dredging  in  California.— J.  E.  Doolittle.      1905 

Bulletin  37.     Gems,  Jewelers'  Materials,  and  Ornamental  Stones  of  California. 

— George  F.  Kunz.      1905: 

First  edition   (without  colored  plates) 

♦Second  edition  (with  colored  plates) 

♦Bulletin  38.     The    Structural    and    Industrial    Materials    of    California. — Wm. 

Forstner,  T.  C.  Hopkins,  C.  Naramore,  L.  H.  Eddy.     1906 

♦Bulletin  39.     Mineral   Production   of   California,   by  Counties,    1904. — Chas.   G. 

Yale.      (Tabulated  sheet)   

♦Bulletin  40.     Mineral    Production    of    California    for    Eighteen    Years. — Chas. 

G.  Yale.      1904.     (Tabulated  sheet) 

♦Bulletin  41.     Mines    and    Minerals    of    California,    for    1904. — Chas.    G.    Yale. 

(Statistical)    

♦Bulletin  42.     Mineral  Production  of  California,  by  Counties.      1905. — Chas.  G. 

Yale.     (Tabulated  sheet) 

♦Bulletin  43.     Mineral  Production  of  California  for  Nineteen  Years. — Chas.  G. 

Yale.     1905.      (Tabulated  sheet) 

♦Bulletin  44.     Mines    and    Minerals    of    California,    for    1905. — Chas.    G.    Yale. 

(Statistical) 

♦Bulletin  45.     Auriferous  Black  Sands  of  California. — J.  A.  Edman.     1907 

Bulletin  46.     General  Index  to  Publications  of  the  State  Mining  Bureau. — Com- 
piled by  Chas.  G.  Yale.     1907 

♦Bulletin  47.     Mineral   Production  of  California,   by  Counties,   1906. — Chas.   G. 

Yale.     (Tabulated  sheet) 

♦Bulletin  48.     Mineral   Production   of   California  for  Twenty  Years. — Chas.   G. 

Yale.     1906.     (Tabulated  sheet) 


Price 
$0.5( 


$0 


PUBLICATIONS. 


119 


Ictin  49. 

letin  50. 

letln  51. 

letln  52. 


LIGATIONS  OF  THE  CALIFORNIA  STATE  MINING  BUREAU— Continued. 
Asterisk    (*)    indicates  the  publication  Is  out  of  print.  Price. 

Mines    and    Minerals    of    California,    for    1906. — Chas.    G.    Yale. 

(Statistical)   

The   Copper   Resources   of  California. — A.    Hausmann,   J.    Krutt- 

schnitt,  Jr.,  W.  E.  Thome,  J.  A.  Edman.     1908 $1.00 

Mineral    Production    of    California,    by    Counties,    1907. — D.    H. 

Walker.     (Tabulated  sheet) 

Mineral  Production  of  California  for  Twenty-one  Years. — D.  H. 

Walker.     1907.     (Tabulated  sheet) 

ineral  Production  of  California  for  1907,  with  County  Maps — 

D.H.Walker.     1908.     (Statistical) 

ineral    Production    of    California,    by    Counties,    1908. — D.    H. 

Walker.      (Tabulated  sheet) 

Mineral  Production  of  California  for  Twenty-two  years. — D.   H. 

Walker.     1908.     (Tabulated  sheet) 

Mineral   Production   for   1908,    County   Maps,    and   Mining   Laws 

of  California. — D.H.Walker.     1909.     (Statistical) 

Gold    Dredging   in    California. — W,    B.    Winston,    Charles    Janin. 

1910 

Mineral    Production    of    California,    by    Counties,    1909. — D.    H. 

Walker.     (Tabulated  sheet) 

Mineral  Production  of  California  for  Twenty-three  Years. — D.  H. 

Walker.     1909.     (Tabulated  sheet) 

Mineral    Production   for   1909,    County   Maps,    and   Mining  Laws 

of  California. — D.  H.  Walker.     1910.      (Statistical) 

Mineral  Production  of  California,  by  Counties,  for  1910. — D.  H. 

Walker.     (Tabulated  sheet) 

Mineral  Production  of  California  for  Twenty-four  Years. — D.  H. 

Walker.     1910.     (Tabulated  sheet) 

Petroleum  in  Southern  California. — P.  W.  Prutzman.     1912 .75 

Mineral  Production  for  1911. — E.  S.  Boalich,  Statistician.     1912__     

Mineral  Production  for  1912. — E.  S.  Boalich.      1913 

Mining  Laws  (United  States  and  California).     1914 

Minerals  of   California. — A.    S.    Eakle.     1914 

Mineral  Production  for  1913. — E.  S.  Boalich.      1914 

Petroleum  Industry  of  California  with  Folio  of  Maps  (18x22  in.) 

— R.  P.  McLaughlin  and  C.  A.  Waring.      1914 2.00 

Mineral  Production  for  1914,  with  Mining  Law  Appendix.      1915.      

California  Mineral  Production  for  1915,  with  Mining  Law  Appen- 
dix and  Maps. — Walter  W.  Bradley.     1916 

Geologic  Formations  of  California. — James  Perrln  Smith.     1917. 

(For  Map,  see  below) .25 

Report  of  Operations  of  Department  of  Petroleum  and  Gas  for 

1915-1916. — R.  P.  McLaughlin.     1917 

California    Mineral    Production   for    1916,    with    County   Maps. — 

Walter  W.  Bradley.     1917 

Mining  Laws,  United  States  and  California.     1917 

Manganese   and   Chromium    in    California. — ^Walter  W.    Bradley, 

Emile    Huguenin,    C.    A.    Logan,    W.    Burling    Tucker,    C.    A. 

Waring.      1918    .50 

Catalogue    of    the    Publications   of    the    California    State    Mining 

Bureau,  1880-1917. — E.  S.  Boalich.     1918 

Quicksilver  Resources  of  California. — Walter  W.  Bradley.     1918—    1.50 

Magnesite  in  California.      (In  press) 

Tungsten,  Molybdenum  and  Vanadium,  in  California.  (In  prep- 
aration)         

Copper  Resources  of  Foothill  Belt,  California.     (In  preparation)—     

Second    Annual    Report    of    the    State    Oil    and    Gas    Supervisor, 

1916-1917. — R.  P.  McLaughlin.     1918 ^ 

California   Mineral    Production    for    1917,    with    County   Maps. — 

Walter  W.  Bradley.     1918 

Third  Annual  Report  of  the  State  Oil  and  Gas  Supervisor,  1917- 

1918. — R.  P.  McLaughlin.      1919 

Platinum    Resources   of   California -50 

California     Mineral     Production     for     1919,     with     County     Map. 

Walter  W.   Bradley.      1919 

Commercial  Minerals  of  California. — ^W.  O.  Castello.      (In  press)      

California    Mineral    Production    for    1919,    with    County    Maps — 

Walter  W.    Bradley.      1920 

PRELIMINARY   REPORTS. 


illetin  63. 

Uetin  64. 

Illetin  65. 

Illelin  66. 

Illetin  67. 

Illetin  68. 

lletin  69. 

Illetin  70. 

lletin  71. 

lletin  72. 

Illetin  73. 

lletin  74. 


lletin  77. 

lletin  78. 
lletin  79. 
;ietin  80. 

lletin  81. 
lletin  82. 


letin  87 
letin  88 


^liminary  Report    No.    1.     Notes    on    Damage    by   Water    in    California    Oil 

Fields,  Dec,  1913.     By  R.  P.  McLaughlin 

liminary  Report    No.    2.     Notes    on    Damage    by   Water    in    California   Oil 

Fields,  Mar.,   1914.     By  R.  P.  McLaughlin 

iliminary  Report  No.  3.     Manganese  and  Chromium,  1917.     By  E.  S.  Boalich 
/liminary    Report    No.    3.     Manganese    and    Chromium.     By   E.    S.    Boalich. 

/  (Second  edition) 

^liminary  Report  No.  4.     Tungsten,  Molybdenum  and  Vanadium,   1918.     By 

f  E.  S.  Boalich  and  W.  O.  Castello 

'f^liminary  Report   No.    5.     Antimony,    Graphite,    Nickel.    Potash,    Strontium, 

Tin,  1918.     By  E.  S.  Boalich  and  W.  O.  Castello 

Preliminary  Report  No.  6.     Review  of  Mining  in  California  during  1919 

'reliminary  Report  No.  7.     Clay  Industry  of  California 


120  CALIFORNIA  STATE  MINING  BUREAU. 

PUBLICATIONS    OF    THE    CALIFORNIA    STATE     MINING     BUREAU— Continued. 
REGISTERS  OF   MINES  WITH    MAPS. 

Asterisk  (*)   indicates  tlie  publication  is  out  of  print.  Price 

Amador  County $.25 

Butte  County .25 

♦Calaveras  County 

*E1  Dorado  County 

*Inyo  County 

♦Kern  County 

♦Lake  County 

♦Mariposa   County 

♦Nevada  County 

♦Placer  County 

♦Plumas  County 

♦San  Bernardino  County . 

♦San  Diego  County 

Santa  Barbara  County .25 

♦Shasta  County 

♦Sierra  County 

♦Siskiyou  County 

♦Trinity  County 

♦Tuolumne  County 

Yuba  County .25 

Register  of  Oil  Wells  (with  map),  Los  Angeles  City .35 

OTHER    MAPS. 

♦California,  Showing  Mineral  Deposits  (50x60  in.) — mounted 

Forest  Reserves  in  California — 

Mounted   .50 

Unmounted     .30 

♦Mineral  and  Relief  Map  of  California 

El  Dorado  County,  Showing  Boundaries  of  National  Forests .20 

Madera  County,  Showing  Boundaries  of  National  Forests .20 

Placer  County,  Showing  Boundaries  of  National  B'orests .20 

Shasta  County,  Showing  Boundaries  of  National  Forests .20 

Sierra  County,  Showing  Boundaries  of  National  Forests .20 

Siskiyou  County,  Showing  Boundaries  of  National  Forests .20 

♦Trinity  County,  Showing  Boundaries  of  National  Forests 

Tuolumne  County,  Showing  Boundaries  of  National  Forests .20 

♦Mother  Lode  Region 

Desert  Region  of  Southern  California .10 

Minaret  Region,   Madera  County .20 

Copper  Deposits  in  California .05 

Calaveras  County .25 

Lake  County .25 

Tuolumne  County '  ',25 

Geological  Map  of  California  (mounted) — 50x60  inches 2.50 

Geological  Map  of  Inyo  County .60 

OIL  FIELDS  MAPS. 

The  following  maps  of  the  oil  fields  of  the  state  have  been  completed  and  placed 
on  sale : 

The  prices  of  the  maps  are  75  cents  per  copy,  with  the  exception,  of  the  Sargent 
oil  map,  which  is  50  cents.     These  prices  include  postage. 
Map  No.     1 — Sargent,  Santa  Clara  County. 

Map  No.     2 — Santa  Maria,  including  Cat  Caiion  and  Los  Alamos. 
Map  No.     3 — Santa  Maria,   including  Casmalia  and  Lompoc. 
Map  No.     4 — ^Whittier-Fullertoh,    including   Olinda,    Brea   Caflon,    Puente   Hills,   East 

Coyote,  and  Richfield. 
Map  No.     5 — Whittier-F'ullerton,  including  Whittier,  West  Coyote,  and  Montebello. 
Map  No.     6 — Salt  Lake,  Los  Angeles  County. 
Map  No.     7 — Sunset  and  San  Emidio,  Kern  County. 
Map  No.     8 — South  Midway   and   Buena  Vista   Hills,    Kern   County. 
Map  No.     9 — North  Midway  and  McKittrick,    Kern   County. 
Map  No.   10 — Belridge  and  McKittrick  Front,  Kern  County. 
Map  No.   11 — Lost   Hills   and  North   Belridge,   Kern   County. 
Map  No.  12 — Devils  Den,  Kern  County. 
Map  No.   13 — Kern  River,  Kern  County. 
Map  No.   14 — Coalinga,  Fresno  County. 
Map  No.   15 — Elk  Hills.  Kern  County. 
Map  No.   16 — Ventura-Ojai,  Ventura  County. 
Map  No.   17 — Santa  Paula-Sespe  Oil  Fields,  Ventura  County. 
Map  No.   18 — (In  preparation). 
Map  No.   19 — Arroyo  Grande,  San  Luis  Obispo  County. 

DETERMINATION    OF    MINERAL   SAMPLES. 

Samples  (limited  to  three  at  one  time)  of  any  mineral  found  in  the  state  may  be 
sent  to  the  Bureau  for  identification,  and  the  same  will  be  classified  free  of  charge. 
No  samples  will  be  determined  if  received  from  points  outside  the  state.  It  must  be 
understood  that  no  assays  or  quantitative  determinations  will  be  made.  Samples 
should  be  in  lump  form  if  possible,  and  marked  plainly  with  name  of  sender  on  out- 
side of  package,  etc.  No  samples  will  be  received  unless  delivery  charges  are  prepaid. 
A  letter  should  accompany  sample,  giving  locality  where  mineral  was  found  and  the 
nature  of  the  Information  desired. 


INDEX. 


Page 

Aluminum     12 

Amphibole         17 

Anglesite 54 

Antimony     14 

Apatite   — 73 

Appendix    105 

Arsenic 16 

Arsenopyrite     16 

Asbestos    : 17 

Asphalt     19 

Azurite 34 

Barite 30 

Barium 20 

Barytas 20 

Bauxite    — 12 

Bibliography    112-115 

On   Economic  Geology 113 

On  Mineralogy     112 

On  Prospecting    114 

Biotite 61 

Bismite 23 

Bismuth     22 

Bismuthinite 23 

Bismutite 23 

Bituminous  Rock 19 

Benitoite     44 

'Blister   Copper'    35 

Borax    24 

Bornite 34 

Brass 33 

Braunite     . 58 

Brick 31 

Bronze 33 

Cadmium    _. . 25 

Calamine 102 

Carnotite    100 

Cassiterite 96 

Celestite    91 

Cement    1 26,   27 

Cerussite     54 

Chalcedony 44 

Chalcocite ; 34 

Chalcopyrite 34 

Chalk     28 

Chromite 29 

Chromium 28 

Chrysotile    17 

Cinnabar     81 

Clay    31 

Coal    32 

Colemanite     24 

Copper    33 

Corundum    36 

Crushed   Rock   89 

Cryolite     : 40,  41 

Cuprite    34 

^2484  (121) 


122  INDEX. 

Page 

Descloizite    100 

Diamond    44 

Diatomaceous   Earth    28,  49 

Dolomite    37 

Economic  Geology,   Bibliography   on 113 

Emerald    44 

Emery    36 

Everett,  Washington,  production  of  arsenic  at _-  16 

Feldspar     38 

Ferberite — 98 

Fluorite     — 40 

Fluorspar 40 

Franklinite 102 

Fuller's   Earth   __— 41 

Galena    5n 

Galenite    5:! 

Gems   42 

Glauberite     __— 89 

Gold   44 

Granite    45 

Graphite    . 46 

Greenockite 26 

Grinding-Mill  Pebbles 89 

Gypsum   4^ 

Halite    S;] 

Hanksite 89 

Hematite   51,   62 

Hiibnerite 9S 

Information  Bureau,  General 9^ 

Infusorial   Earth 28,  49| 

Iron    : 50| 

Kunzite -- 441 

Laboratory    9; 

Lead     53; 

Lepidolite    61 

Library    . 9 

Lime     27 

Limestone 27 

Limonite    51,  62 

Lithia    __— 60 

Lithopone    20 

Malachite    34. 

Manganese    57 

Manganite    _ — 58 

Magnieslte    55 

Magnetite    — 52 

Marble 59 

Marcasite 80 

Mercury    8  ] 

Metacinnabarite 82 

Mica    60 

Mlorocline    oii 

Millerite 69 

Mineralogy,   Bibliography   on   15  2 

Mineral    Paint    62 

Miscellaneous  Stone 8  9 


INDEX.  123 

Page 

Molybdenite     65 

Molybdenum 63 

Monazite    66,  73 

Muscovite 61 

Native    Copper    34 

Iron   51 

Natron    88 

Natural  Gas 67 

Niccolite -- 69 

Nickel     68 

Niter   70 

Nitrates     70 

Nitrocalcite    71 

Opal 44 

Orpiment    — 16 

Orthoclase    — — 39 

Patronite — _ 100 

Paving  Blocks 89 

Petroleum     — _ — 72 

Petroleum  and  Gas,  Department  of 10 

Phlogopite — 61 

Phosphate    Rock    72 

Platinum   74 

Potash     76 

Potassium 76 

Pottery    31 

Preface    9 

Prospecting,   Books  on 114 

Publications 9 

Psilomelane   57 

Pumice 78 

Pyrite    80 

Pyrites    79 

Pyrolusite _ 58 

Pyrrhotite     , 69,   80 

Quartz    — 84 

Quicksilver 81 

Realgar    -- 16 

Rock    Salt    . 83 

Roscoelite     100 

Ruby 37,  44 

Salt    82 

Saltpeter 70 

Sand 84 

Sandstone     : 84 

Sapphire     37,   44 

Scheelite 98 

Silica 84 

Silver 86 

Slate 86 

Smithsonite    102 

Soapstone     — 94 

Soda ST 

Soda    Niter    — To 

Sodium Ss 

Sodium  Carbonate — : J^^^ 

Sphalerite    102 


124  INDEX. 

t    .^  Page 

Spodumene    — 44 

Stannite    ^ 96 

State  Mining  Bureau  Activities — . 9-11 

General  Information  Bureau 0 

Liaboratory     !» 

Library    1» 

Museum     — 10 

Petroleum  and  Gas,  Department  of 10 

Publications    , 9 

Statistical  Department 10 

War    activities    : — 11 

Statistical    Department    _— 10 

Stibnite   ]  4 

Strontianite    9] 

Strontium     !tO 

Sulphur    92 

Sulphuric   Acid 81 

Talc    . 94 

Tetrahedrite     34 

Thenardite    SS 

Tile     31 

Tin     95 

Topaz     44 

Tourmaline     44 

Trona    SS; 

Tungsten 9  7 

Ulexite    2  1 

Vanadinite 100 

Vanadium 99 

Volcanic  ash — 78 

Tuff    79 

War  Activities  of  State  Mining  Bureau 11 

Willemite    102 

Witherite 21 

Wolframite 9  8 

Wulfenite 54,   64 

Zinc     101 

Zincite     102 


CALIFORNIA    STATE    MIINING    BUREAT 

FERRY  BUILDING,  SAN  FRANCISCO 
FLETCHER  HAMILTON  State  Mineralogist 


?  j 


San  Francisco] 


BULLETIN  No.  88 


[July,  1920 


California 

Mineral  Production 

for  1919 


WITH   COUNTY   M.A.FS 


CALIFORNIA    STATS   PKINTING    OFFICE 

SACBAMENTO 

19  2  0 


